SIP是类似于HTTP的基于文本的协议

SIP是类似于HTTP的基于文本的协议 SIP是类似于HTTP的基于文本的协议。SIP可以减少应用特别是高级应用的开发时间。由于基于IP协议的SIP利用了IP网络，固定网运营商也会逐渐认识到SIP技术对于他们的深远意义。 目录 信令控制协议 历史回顾 SIP 会话构成 323和SIP协议的比较 Java相关技术 编辑本段信令控制协议本目录涉及专业领域知识，部分内容存在争议，已由中国科学院自动化研究所硕士 孙亮核实查证。 查证内容已提供参考资料，点击查看详情。 SIP SIP(Session Initiation Protocol)是一个应用层的信令控制协议。用于创建、修改和释放一个或多个参与者的会话。这些会话a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel [1] 可以是Internet多媒体会议、IP电话或多媒体分发。会话的参与者可以通过组播(multicast)、网状单播(unicast)或两者的混合体进行通信。 使用 SIP，服务提供商可以随意选择组件。不论媒体内容和参与方数量，用户都可以查找和联系对方。SIP 对会话进行协商，以便所有参与方都能够就会话功能达成一致以及进行修改。它甚至可以添加、删除或转移用户。 SIP它既不是会话描述协议，也不提供会议控制功能。为了描述消息内容的负载情况和特点，SIP 使用 Internet 的会话描述协议 (SDP) 来描述终端设备的特点。SIP 自身也不提供服务质量 (QoS)，它与负责语音质量的资源预留协议(RSVP) 互操作。它还与若干个其他协议进行协作，包括负责定位的轻型目录访问协议(LDAP)、负责身份验证的远程身份验证拨入用户服务 (RADIUS) 以及负责实时传输的 RTP 等多个协议。 SIP 的一个重要特点是它不定义要建立的会话的类型，而只定义应该如何管理会a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 话。有了这种灵活性，也就意味着SIP可以用于众多应用和服务中，包括交互式游戏、音乐和视频点播以及语音、视频和 Web 会议。SIP消息是基于文本的，因而易于读取和调试。新服务的编程更加简单，对于设计人员而言更加直观。SIP如同电子邮件客户机一样重用 MIME 类型描述，因此与会话相关的应用程序可以自动启动。SIP 重用几个现有的比较成熟的 Internet 服务和协议，如 DNS、RTP、RSVP 等。不必再引入新服务对 SIP 基础设施提供支持，因为该基础设施很多部分已经到位或现成可用。 对 SIP 的扩充易于定义，可由服务提供商在新的应用中添加，不会损坏网络。网络中基于 SIP 的旧设备不会妨碍基于 SIP 的新服务。例如，如果旧 SIP 实施不支持新的 SIP 应用所用的方法/标头，则会将其忽略。 SIP 独立于传输层。因此，底层传输可以是采用 ATM 的 IP。SIP 使用用户数据报协议(UDP) 以及传输控制协议(TCP)，将独立于底层基础设施的用户灵活地连接起来。a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel SIP 支持多设备功能调整和协商。如果服务或会话启动了视频和语音，则仍然可以将语音传输到不支持视频的设备，也可以使用其他设备功能，如单向视频流传输功能。 通信提供商及其合作伙伴和用户越来越渴求新一代基于 IP 的服务。现在有了 SIP(The Session Initiation Protocol 会话启动协议)，一解燃眉之急。SIP 是不到十年前在计算机科学实验室诞生的一个想法。它是第一个适合各种媒体内容而实现多用户会话的协议，现在已成了 Internet 工程任务组 (IETF) 的。 今天，越来越多的运营商、CLEC(竞争本地运营商)和 ITSP(IP 电话服务商)都在提供基于 SIP 的服务，如市话和长途电话技术、在线信息和即时消息、IP Centrex/Hosted PBX、语音短信、 push-to-talk(按键通话)、多媒体会议等等。独立软件供应商 (ISV) 正在开发新的开发工具，用来为运营商网络构建基于 SIP 的应用程序以及 SIP 软件。网络设备供应商 (NEV) 正在开发支持 SIP 信令和服务a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 的硬件。现在，有众多 IP 电话、用户代理、网络代理服务器、VOIP网关、媒体服务器和应用服务器都在使用 SIP。 SIP 从类似的权威协议,,如 Web超文本传输协议(HTTP) 格式化协议以及简单邮件传输协议(SMTP) 电子邮件协议,,演变而来并且发展成为一个功能强大的新标准。但是，尽管 SIP 使用自己独特的用户代理和服务器，它并非自成一体地封闭工作。SIP 支持提供融合的多媒体服务，与众多负责身份验证、位置信息、语音质量等的现有协议协同工作。 SIP 较为灵活，可扩展，而且是开放的。它激发了 Internet 以及固定和移动 IP 网络推出新一代服务的威力。SIP 能够在多台 PC 和电话上完成网络消息，模拟 Internet 建立会话。 与存在已久的国际电信联盟(ITU) SS7 标准(用于呼叫建立)和 ITU H.323 视频协议组合标准不同，SIP 独立工作于底层网络传输协议和媒体。它规定一个或多个参与方的终端设备如何能够建立、修改和中断连a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 接，而不论是语音、视频、数据或基于 Web 的内容。 SIP 大大优于现有的一些协议，如将 PSTN 音频信号转换为 IP 数据包的媒体网关控制协议(MGCP)。因为 MGCP 是封闭的纯语音标准，所以通过信令功能对其进行增强比较复杂，有时会导致消息被破坏或丢弃，从而妨碍提供商增加新的服务。而使用 SIP，编程人员可以在不影响连接的情况下在消息中增加少量新信息。 例如，SIP 服务提供商可以建立包含语音、视频和聊天内容的全新媒体。如果使用 MGCP、H.323 或 SS7 标准，则提供商必须等待可以支持这种新媒体的协议新版本。而如果使用 SIP，尽管网关和设备可能无法识别该媒体，但在两个大陆上设有分支机构的公司可以实现媒体传输。 而且，因为 SIP 的消息构建方式类似于 HTTP，开发人员能够更加方便便捷地使用通用的编程语言(如 Java)来创建应用程序。对于等待了数年希望使用 SS7 和高级智能网络(AIN) 部署呼叫等待、主叫号码识别以a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel [2]及其他服务的运营商，现在如果使用 SIP，只需数月时间即可实现高级通信服务的部署。 这种可扩展性已经在越来越多基于 SIP 的服务中取得重大成功。Vonage 是针对用户和小企业用户的服务提供商。它使用 SIP 向用户提供 20,000 多条数字市话、长话及语音邮件线路。Deltathree 为服务提供商提供 Internet 电话技术产品、服务和基础设施。它提供了基于 SIP 的 PC 至电话解决，使 PC 用户能够呼叫全球任何一部电话。Denwa Communications 在全球范围内批发语音服务。它使用 SIP 提供 PC 至 PC 及电话至 PC 的主叫号码识别、语音邮件，以及电话会议、统一通信、客户管理、自配置和基于 Web 的个性化服务。 某些权威人士预计，SIP 与 IP 的关系将发展成为类似 SMTP 和 HTTP 与 Internet 的关系，但也有人说它可能标志着 AIN 的终结。迄今为止，3G 界已经选择 SIP 作为下一代移动网络的会话控制机制。 Microsoft 已经选择 SIP 作为其实时通信a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 策略并在 Microsoft XP、Pocket PC 和 MSN Messenger 中进行了部署。Microsoft 同时宣布 CE dot net 的下一个版本将使用基于 SIP 的 VoIP 应用接口层，并承诺向用户 PC 提供基于 SIP 的语音和视频呼叫。 另外，MCI 正在使用 SIP 向 IP 通信用户部署高级电话技术服务。用户将能够通知主叫方自己是否有空以及首选的通信方式，如电子邮件、电话或即时消息。利用在线信息，用户还能够即时建立聊天会话和召开音频会议。使用 SIP 将不断地实现各种功能。 SIP压缩机制 SIP 压缩机制主要是通过改变 SIP 消息的长度来降低时延。典型的 SIP 消息的大小由几百到几千字节，为了适合在窄带无线信道上传输，IMS对SIP进行了扩展，支持SIP消息的压缩。当无线信道一定时， 一条SIP消息所含帧数 k仅取决于消息大小。从时延模型可以看出，不仅影响 SIP 消息传输时延， 还影响SIP重传的概率， 对自适a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 应的定时器来说，k还成了影响定时器初值 [3] 的关键因素。 SIP的应用 google 发布世界上首个开源的Html5 sip 客户端 HTML5 SIP客户端是一款开源的，完全利用JavaScript编写的集社交(FaceBook，Twitter，Google+)，在线游戏，电子商务等应用于一体。无扩展，无插件或是必备的网关，视频堆栈技术依赖于WebRTC。如同主页里的Demo视频演示，你可以轻松实现Chrome和IOS/Android移动设备之间的实时视频/音频通话。 该客户端是一项在浏览器中可被用来连接任意SIP或者IMS网络进行拨打和接收音频/视频通话及即时信息技术。该协议解析器(SIP，SDP...)通过使用Ragel查找表进行了高度优化，很适合硬件(内存和运算能力)受限的嵌入式系统使用。 Html5 sip 客户端 新特性包括: 支持Audio / Video通话功能; a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 支持即时信息; Presence; 呼叫保持/恢复; 显示呼叫转移; 支持多个账号; 双音多频信号(DTMF)使用SIIP INFO 历史回顾 SIP 出现于二十世纪九十年代中期，源于哥伦比亚大学计算机系副教授Henning Schulzrinne 及其研究小组的研究。Schulzrinne 教授除与人共同提出通过 Internet 传输实时数据的实时传输协议(RTP) 外，还与人合作编写了实时流传输协议 (RTSP) 标准提案，用于控制音频视频内容在 Web 上的流传输。 Schulzrinne 本来打算编写多方多媒体会话控制 (MMUSIC) 标准。1996 年，他向 IETF 提交了一个草案，其中包含了 SIP 的重要内容。1999 年，Shulzrinne 在提交的新标准中删除了有关媒体内容方面的无关内容。随后，IETF 发布了第一个 SIP 规范，即 RFC 2543。虽然一些供应商表示了担忧，a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 认为 H.323 和 MGCP 协议可能会大大危及他们在 SIP 服务方面的投资，IETF 继续进行这项工作，于 2001 年发布了 SIP 规范 RFC 3261。 RFC 3261 的发布标志着 SIP 的基础已经确立。从那时起，已发布了几个 RFC 增补版本，充实了安全性和身份验证等领域的内容。例如，RFC 3262 对临时响应的可靠性作了规定。RFC 3263 确立了 SIP代理服务器的定位规则。RFC 3264 提供了提议/应答模型，RFC 3265 确定了具体的事件通知。 早在 2001 年，供应商就已开始推出基于 SIP 的服务。今天，人们对该协议的热情不断高涨。Sun Microsystems 的 Java Community Process 等组织正在使用通用的 Java 编程语言定义应用编程接口 (API)，以便开发商能够为服务提供商和企业构建 SIP 组件和应用程序。最重要的是，越来越多的竞争者正在借助前途光明的新服务进入 SIP 市场。SIP 正在成为自 HTTP 和 SMTP 以来最为重要的协议之一。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel SIP 的优点:类似 Web 的可扩展开放通信 使用 SIP，服务提供商可以随意选择标准组件，快速驾驭新技术。不论媒体内容和参与方数量，用户都可以查找和联系对方。SIP 对会话进行协商，以便所有参与方都能够就会话功能达成一致以及进行修改。它甚至可以添加、删除或转移用户。 不过，SIP不是万能的。它既不是会话描述协议，也不提供会议控制功能。为了描述消息内容的负载情况和特点，SIP 使用 Internet 的会话描述协议 (SDP) 来描述终端设备的特点。SIP 自身也不提供服务质量 (QoS)，它与负责语音质量的资源保留设置协议 (RSVP) 互操作。它还与若干个其他协议进行协作，包括负责定位的轻型目录访问协议 (LDAP)、负责身份验证的远程身份验证拨入用户服务 (RADIUS) 以及负责实时传输的 RTP 等多个协议。 SIP 规定了以下基本的通信要求: 1( 用户定位服务 2( 会话建立 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 3( 会话参与方管理 4( 特点的有限确定 SIP 会话构成 SIP 会话使用多达四个主要组件:SIP 用户代理、SIP 注册服务器、SIP 代理服务器和 SIP 重定向服务器。这些系统通过传输包括了 SDP 协议(用于定义消息的内容和特点)的消息来完成 SIP 会话。下面概括性地介绍各个 SIP 组件及其在此过程中的作用。 3.1、SIP 用户代理 SIP 用户代理(UA) 是终端用户设备，如用于创建和管理 SIP 会话的移动电话、多媒体手持设备、PC、PDA 等。用户代理客户机发出消息。用户代理服务器对消息进行响应。 3.2、SIP 注册服务器 SIP 注册服务器是包含域中所有用户代理的位置的数据库。在 SIP 通信中，这些服务器会检索参对方的 IP 地址和其他相关信息，并将其发送到 SIP 代理服务器。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 3.3、SIP 代理服务器 SIP 代理服务器接受 SIP UA 的会话请求并查询 SIP 注册服务器，获取收件方 UA 的地址信息。然后，它将会话邀请信息直接转发给收件方 UA(如果它位于同一域中)或代理服务器(如果 UA 位于另一域中)。 3.4、SIP 重定向服务器 SIP 重定向服务器允许 SIP 代理服务器将 SIP 会话邀请信息定向到外部域。SIP 重定向服务器可以与 SIP 注册服务器和 SIP 代理服务器同在一个硬件上。 以下几个情景说明 SIP 组件之间如何进行协调以在同一域和不同域中的 UA 之间建立 SIP 会话: 在同一域中建立 SIP 会话 下图说明了在预订同一个 ISP 从而使用同一域的两个用户之间建立 SIP 会话的过程。用户 A 使用 SIP 电话。用户 B 有一台 PC，运行支持语音和视频的软客户程序。加电后，两个用户都在 ISP 网络中的 SIP 代理服务器上注册了他们的空闲情况和 IP a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 地址。用户 A 发起此呼叫，告诉 SIP 代理服务器要联系用户 B。然后，SIP 代理服务器向 SIP 注册服务器发出请求，要求提供用户 B 的 IP 地址，并收到用户 B 的 IP 地址。SIP 代理服务器转发用户 A 与用户 B 进行通信的邀请信息(使用 SDP)，包括用户 A 要使用的媒体。用户 B 通知 SIP 代理服务器可以接受用户 A 的邀请，且已做好接收消息的准备。SIP 代理服务器将此消息传达给用户 A，从而建立 SIP 会话。然后，用户创建一个点到点 RTP 连接，实现用户间的交互通信。 title 1.呼叫用户 B a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 2(查询B 在哪里 3(响应B 的 SIP 地址 4(呼叫 5(响应 6(响应 7( 多媒体通道已建立 在不同的域中建立 SIP 会话 本情景与第一种情景的不同之处如下。用户 A 邀请正在使用多媒体手持设备的用户 B 进行 SIP 会话时，域 A 中的 SIP 代理服务器辨别出用户 B 不在同一域中。然后，SIP 代理服务器在 SIP 重定向服务器上查询用户 B 的 IP 地址。SIP 重定向服务器既可在域 A 中，也可在域 B 中，也可既在域 A 中又在域 B 中。SIP 重定向服务器将用户 B 的联系信息反馈给 SIP 代理服务器，该服务器再将 SIP 会话邀请信息转发给域 B 中的 SIP 代理服务器。域 B 中的 SIP 代理服务器将用户 A 的邀请信息发送给用户 B。用户 B 再沿邀请信息经由的同一路径转发接受邀请的信息。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel title 1. 呼叫用户 B 2( 询问B 中的用户 3( 响应 4( 呼叫域 B 的 SIP 代理 5( 查询B 在哪里 6( 用户 B 的地址 7( 代理呼叫 8( 响应 9. 响应 10(响应 11(多媒体通道已建立 无缝、灵活、可扩展:展望 SIP 未来 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel SIP 能够连接使用任何 IP 网络(有线 LAN 和 WAN、公共 Internet 骨干网、移动 2.5G、3G 和 Wi-Fi)和任何 IP 设备(电话、PC、PDA、移动手持设备)的用户，从而出现了众多利润丰厚的新商机，改进了企业和用户的通信方式。基于 SIP 的应用(如 VOIP、多媒体会议、push-to-talk(按键通话)、定位服务、在线信息和 IM)即使单独使用，也会为服务提供商、ISV、网络设备供应商和开发商提供许多新的商机。不过，SIP 的根本价值在于它能够将这些功能组合起来，形成各种更大规模的无缝通信服务。 使用 SIP，服务提供商及其合作伙伴可以定制和提供基于 SIP 的组合服务，使用户可以在单个通信会话中使用会议、Web 控制、在线信息、IM 等服务。实际上，服务提供商可以创建一个满足多个最终用户需求的灵活应用程序组合，而不是安装和支持依赖于终端设备有限特定功能或类型的单一分散的应用程序。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 通过在单一、开放的标准 SIP 应用架构下合并基于 IP 的通信服务，服务提供商可以大大降低为用户设计和部署基于 IP 的新的创新性托管服务的成本。它是 SIP 可扩展性促进本行业和市场发展的强大动力，是我们所有人的希望所在。 H(323和SIP协议的比较 简介 H.323和SIP分别是通信领域与因特网两大阵营推出的协议。H.323企图把IP电话当作是众所周知的传统电话，只是传输方式发生了改变，由电路交换变成了分组交换。而SIP协议侧重于将IP电话作为因特网上的一个应用，较其它应用(如FTP，E-mail等)增加了信令和QoS的要求，它们支持的 业务基本相同，也都利用RTP作为媒体传输的协议。但H.323是一个相对复杂的协议。 H.323采用基于ASN.1和压缩编码规则的二进制方法表示其消息。ASN.1通常需要特殊的代码生成器来进行词法和语法分析。而SIP的基于文本的协议，类似于HTTP。基于a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 文本的编码意味着头域的含义是一目了然的，如From、To、Subject等域名。这种分布式、几乎不需要复杂的文档说明的标准规范风格，其优越性已在过去的实践中得到了充分的证明(现在广为流行的邮件协议SMTP就是 这样的一个例子)。SIP的消息体部份采用SDP进行描述，SDP中的每一项格式为=，也比较简单。 在支持会议电话方面，H.323由于由多点控制单元(MCU)集中执行会议控制功能，所有参加会议终端都向MCU发送控制消息，MCU可能会成为颈，特别是对于具有附加特性的大型会议;并且H.323不支持信令的组播功能，其单功能限制了可扩展性，降低了可靠性。而SIP设计上就为分布式的呼叫模型，具有分布式的组播功能，其组播功能不仅便于会议控制，而且简化了用户定位、群组邀请等，并且能节约带宽。但是H.323的集中控制便于计费，对带宽的管理也比较简单、有效。 H.323中定义了专门的协议用于补充业务，如H.450.1、H.450.2和H.450.3等。a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel SIP并未专门定义的协议用于此目的，但它很方便地支持补充业务或智能业务。只要充分利用SIP已定义的头域(如Contact头域)，并对SIP进行简单的扩展(如增加几个域)，就可以实现这些业务。例如对于呼叫 转移，只要在BYE请求消息中添加Contact头域，加入意欲转至的第三方地址就可以实现此业务。对 于通过扩展头域较难实现的一些智能业务，可在体系结构中增加业务代理，提供一些补充服务或与 智能网设备的接口。 在H.323中，呼叫建立过程涉及到第三条信令信致到:RAS信令信道、呼叫信令信道和H.245控制信道。通过这三条信道的协调才使得H.323的呼叫得以进行，呼叫建立时间很长。在SIP中，会话请求过程和媒体协商过程等一起进行。尽管H.323v2已对呼叫建立过程作了改进，但较之SIP只需要1.5个回路时延来建立呼叫，仍是无法相比。H.323的呼叫信令通道和H.245控制信道需要可靠的传 输协议。而SIP独立于低层协议，一般使用UDP等无法连接的协议，用自a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 己信用层的可靠性机制来保 证消息的可靠传输。 总之，H.323沿用的是传统的实现电话信令模式，比较成熟，已经出现了不少H.323产品。H.323符合通信领域传统的设计思想，进行集中、层次控制，采用H.323协议便于与传统的电话网相连。SIP协议借鉴了其它因特网的标准和协议的设计思想，在风格上遵循因特网一贯坚持的简练、开放、兼容和可扩展等原则，比较简单。 以下针对它们的应用目标、标准结构、系统组成以及系统实现的难易程度等几个方面进行简单分析。 4.1、标准的应用目标 h.323标准是itu-t组织 1996年在h.320/h.324的基础上建立起来的，其应用目标是，在基于ip的网络环境中，实现可靠的面向音视频和数据的实时应用。目前经过多年的技术发展和标准的不断完善，h.323已经成为被广大的itu成员以及客户所接受的一个成熟标准族。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel sip标准是itef组织在1999年提出的，其应用目标是在基于internet环境，实现数据、音视频实时通讯，特别是通过internet将视频通讯这种应用大众化，引入到千家万户。由于sip协议相对于h.323而言，相对简单、自由，厂商可以使用相对小的成本就可以构造满足应用的系统。例如仅仅使用微软基于sip协议的msn，和rtc就可以构造一个简单的，基于internet应用环境的视频通讯环境。这样网络运营商就可以在尽量少的成本基础上，利用现有的网络资源开展视音频通讯业务的扩展工作。 4.2、标准的体系结构 h.323是一个单一标准，而不是一个关于在ip环境中实时多媒体应用的完整标准族，对于呼叫的建立、管理以及所传输媒体格式等各个方面都有完善而严格的规定。一个遵守h.323标准建立的多媒体系统，可以保证实现客户稳定完善的多媒体通讯应用。 sip标准严格意义上讲是一个实现实时多媒体应用的信令标准，由于它采用了基于文a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 本的编码方式，使得它在应用上，特别是点到点的应用环境中，具有极大的灵活性、扩充性以及跨平台使用的兼容性，这一点使得运营商可以十分方便的利用现有的网络环境实现大规模的推广应用。 但是sip协议自身不支持多点的会议功能以及管理和控制功能，而是要依赖于别的协议实现，影响了系统的完备性，特别是对于需要多点通讯的要求，应用单纯的sip系统难以实现。针对这些不足，以radvison公司为首的itu-t sg16小组提出了sip的运用规范，并实现了sip和h.323之间的互通互联，并成功的解决了sip在多点环境下的应用难。 4.3、系统的组成结构 首先，在系统主要组成成员的功能性方面进行类比，sip的ua等价于一个h.323的终端，实现呼叫的发起和接收，并完成所传输媒体的编解码应用;sip代理服务器、重定向服务器以及注册服务器的功能则等价于a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel h.323的gatekeeper，实现了终端的注册、呼叫地址的解析以及路由。 其次，虽然在呼叫信令和控制的具体实现上不同，但一个基于sip的呼叫流程与h.323的q931相类似，sip所采用的会话描述协议(sdp)则类似于h.323中的呼叫控制协议h.245。 4.4、系统实现的难易性 h.323标准的信令信息是采用符合asn.1 per的二进制编码，并且在连接实现全过程都要严格标准的定义，系统的自由度小，如要实现大规模的应用，需要对整个网络的各个环节进行规划。 sip标准的信令信息是基于文本的，采用符合iso10646的utf-8编码，并且全系统的构造结构相对灵活，终端和服务器的实现也相对容易成本也较低，从网络运营商的角度考虑，构造一个大规模视频通讯网络，采用sip系统的成本要廉价许多，而且也更具有可实现性。 4.5、总 结 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 通过对sip和h.323协议之间进行比较，我们不难看出，h.323和sip之间不是对立的关系，而是在不同应用环境中的相互补充。sip作为以internet应用为背景的通讯标准，是将视频通讯大众化，引入千家万户的一个有效并具有现实可行性的手段。而h.323系统和sip系统有机结合，又确保了用户可以在构造相对廉价灵活的sip视频系统的基础上，实现多方会议等多样化的功能，并可靠的实现sip系统与h.323系统之间的互通，在最大程度上满足用户对未来实时多媒体通信的要求。 编辑本段Java相关技术 5.1、开源项目 开源软件无线电技术对通信的各个行行业业影响颇深，SIP也不例外。GNU Radio 是免费的软件开发工具套件。它提供信号运行和处理模块，用它可以在易制作的低成本的射频(RF)硬件和通用微处理器上实现软件定义无线电。这套套件广泛用于业余爱好者，学术机构和商业机构用来研究和构建无a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 线通信系统。GNU Radio 的应用主要是用 Python 编程语言来编写的。但是其核心信号处理模块是C++在带浮点运算的微处理器上构建的。因此，开发者能够简单快速的构建一个实时、高容量的无线通信系统。尽管其主要功用不是仿真器，GNU Radio 在没有射频 RF 硬件部件的境况下支持对预先存储和(信号发生器)生成的数据进行信号处理的算法的研究。 5.2、Java 在这里,我只讨论与java相关的SIP技术，其实实现SIP的技术有多种，比如CGI. java为SIP提供了非常好的支持，JCP(Java Community Process)组织推动开发的一套基于Java技术的API:JAIN API(Java API for Integrated Networks),它包含JAIN SIP(JAIN SIP Lite)和SIP Servlet(JSR 116),SIP for J2ME,三个规范. 以下为与java相关的SIP技术: JAIN SIP API (JSR 32) a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel SIP Servlet API (JSR 116) JAIN SIP Lite (JSR 125) SIP API for J2ME (JSR 180) JAIN SIMPLE Presence (JSR 164) JAIN SIMPLE Instant Messaging (JSR 165) JAIN SDP (JSR 141) SIP描述协议 Java Media Framework for RTP (J2SE可选包，并非JAIN的) SIP for J2ME:(JSR 180 ) JAIN SIP API主要提供了J2SE平台的SIP 协议栈的实现，主要面向桌面的J2SE应用; SIP Servlet API主要为面向服务端的SIP 程序提供了一个API规范，目前实现了该规 范的应用服务器有BEA Weblogic SIP Server和Micromethod,还有Jiplet Container,至于如何开发sip servlet,可 参见参考资料.SIP for J2ME主要为面向手 机的CLDC设备的J2ME客户端.它们之间的 差别在参考资料[6]中讲解得很详细. 其它Java相关技术: a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel jiplet: 一个支持sip servlet的应用服 务器 nist-sip SIP Libraries and Tools JAIN Service Logic Execution Environment (SLEE) 参考资料 , 1( 多媒体会议 (百度百科[引用日期 2012-12-26]( , 2( 波克申科 (作者), 梅耶尔(Georg Mayer) (作者), 望育梅 (译者), 周胜 (译者) (《IMS:IP多媒体子系统概念 与服务(原书第3版)》:机械工业出版 社，2011年( , 3( IMS中SIP会话建立时延的研究 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel IMS，英文缩写。IMS(IP Multimedia Subsystem)是IP多媒体系统,是一种全新的多媒体业务形式，它能够满足现在的终端客户更新颖、更多样化多媒体业务的需求。 目录 [隐藏 ] 1 概述 2 发展历程 3 应用 4 安全问题分析 5 多种含义 6 参考资料 IMS IMS(IP Multimedia Subsystem)是IP多媒体系统,是一种全新的多媒体业务形式，它能够满足现在的终端客户更新颖、更多样化多媒体业务的需求。目前，IMS被认为是下一代网络的核心技术，也是解决移动与固网融合，引入语音、数据、视频三重融合等差异化业务的重要方式。但是，目前全球IMS网络多数处于初级阶段，应用方式也处于业界探讨当中。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 1. IMS - 概述 IMS最初是由3GPP(第三代合作伙伴计划)组织制定的一项3G网络核心技术标准。现在这项标准已为ITU-T(国际电联标准化部门)和ETSI(欧洲电信标准化委员会)认可，被纳入下一代网络(NGN)的核心框架之中。它被认为是未来实现固定网和移动网融合(FMC)的重要技术基础。 IMS的体系结构分为业务层、控制层和链接层。业务层由应用(和内容)服务器组成，负责为用户提供增值服务。控制层由网络控制服务器组成，负责管理呼叫或会话的设定、修改和释放。在这些服务器中最重要的是具有呼叫会话控制功能(CSCF)的SIP服务器。在控制层中，还配置了计费、运营维护等多功能。边界网关负责与其他运营商网络或其他类型网络之间的互通。连接层由用于骨干网和接入网的路由器及交换机组成。 IMS符合下一代网络把呼叫控制和传输分离的要求;它基于SIP，与接入无关，符合网络向“多种终端——多种接入——统一控制核心网——多种应用的网络体系结构”演变a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 的发展方向，使得多种业务能同时进行交互，以形成一个更加灵活的通信平台。不仅可以实现人到内容的多媒体通信，还能实现人到人的多媒体通信。IMS将最终融合固定网、移动网、企业网、无线网等各种网络，简化网络结构，支持更丰富的定制化业务。 IMS 2. IMS - 发展历程 国际第三代移动通信组织3GPP一直在进行它称为IP多媒体子系统IMS的标准化研究。在3GPP的文件R5中，IMS是UMTS核心网络中提供端到端多媒体业务和集群多媒体业务的中心。在3GPP的R6中，IMS已经被定义为支持所有IP接入网的多媒体业务核心网，可以支持任何一种移动的或固定的、有线的或无线的IP-CAN(IP Connectivity Ac a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel cess Networks)，包括W-CDMA，CDMA2000，Ethernet，xDSL以及Wireless LAN等等。 IMS由控制多媒体会话的网络实体组成，在UMTS中IMS是提供IP多媒体服务的核心。IP多媒体服务使用GPRS网络来进行传输。网络提供者同时为IP多媒体服务提供传输实体和网络控制实体。网络结构同时允许为第三方提供附加的IP多媒体服务。 在UMTS版本5或更高的版本中，新增加的主要内容就是添加了两个全新的具有重要能力的IMS。第一，增加类似呼叫状态控制功能(CSCF)的新的网络实体来提供基本的IP多媒体服务，例如在两个用户间的多媒体会话的发起。第二，相互兼容已经发展到可以提炼一些网络实体能力的阶段，例如开放业务接入(OSA)服务能力。利用基本的IP多媒体服务和网络提供的能力，OSA服务能力的功能被期望能够激励第三方新的IP多媒体服务的产生。 一个IMS包括一个或多个CSCF、媒体网关控制功能(MGCF)、IMS媒体网关、多媒体资源功能处理器(MRFC)、订阅位置功能、中断网a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 关控制功能(BGCF)和应用服务器。我们下面解释IMS如何实现其主要功能和如何为UMTS增加支持多媒体业务。 IPv6--IMS的信令和会话业务都是通过IP承载的，但是，并不是任何版本的IP都是可以使用的，IMS要求只有IPv6才能在IMS域中使用。虽然这将使UMTS这一全球第一商业系统广泛地发展IPv6，但是这仍将是一个大胆的要求，因为: IMS中的IP寻址与分组域骨干网中使用的(例如IPv4)和电路域中使用的是不同的，所以IPv6和IPv4互通的问题需要解决。 用于移动台接入IP多媒体服务的IP寻址范围必须在IMS寻址域内，这个寻址域是在建立好IP连接时激活的PDP上下文中安排好的。IP地址可以从服务域而不是归属域的GGSN中获得，从路由的效率来考虑，这是一个优点。 呼叫/会话控制--CSCF使用SIP在呼叫控制中发挥了核心作用。CSCF可以比作电路域语音通话中移动交换中心的信令部分和控制部分。除了语音通信之外，它还能支持多媒a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 体会话。SIP是在移动台和CSCF之间、CSCF之间、CSCF和MGCF之间、CSCF和应用服务器之间有关信令方面的协议。CSCF起到了很多作用:作为代理CSCF(P-CSCF)，这是移动台和IMS连接最初的一点;作为提供服务的CSCF(S-CSCF)，可以用于会话控制;作为询问CSCF(I-CSCF)，这是网络中各个移动台的有关IMS信令的一个主要的连接点。 PSTN互通--当会话的一端为IMS用户，而会话的另一端是公共电话交换网用户时,网络需要四个新的功能实体-IMS媒体网关、MGCF、信令网关和BGCF。BGCF具有支持PSTN与PS域之间的呼叫的功能。媒体网关用来完成在两端用不同格式编码的媒体信号的翻译。MGCF控制IMS媒体网关，提供在基于SIP的和基于ISUP信令之间应用级的信令翻译，并且与S-CSCF进行通信。传输级的在基于IP的和基于SS7的信令翻译由SGW完成。BGCF识别网络和网络中的MGCF，并确定进入PSTN的位置。 处理用户签订的信息和用户状态的信息--归属用户服务器(HSS)是主要的数据库，它a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 存储用户签订的业务信息和本地信息。它可以被考虑为一个增强型GSM网络中的归属位置寄存器。因为在网络中有几个HSS存在，在注册和会话建立过程中，为了找到有目标用户信息的HSS，用户位置功能被CSCF询问。用户位置功能不需要在单一的HSS环境下实现，因为CSCF知道哪一个HSS会被使用。 可以使用各种不同的应用服务器，包括基于SIP的应用服务器和OSA应用服务器，这些应用服务器可以实现各种服务，例如语音提示服务和预付费服务。支持多种服务的应用服务器还可以促进新的业务的产生。在这两种情况下，SIP为S-CSCF的信令服务，然而，在一个OSA应用服务器的例子中，一个OSA容量服务器应该插入在OSA应用服务器和S-CSCF之间。 多方会议-媒体资源功能处理器(MRFP)和媒体资源功能控制器(MRFC)支持多方多媒体会议，并能体现媒体资源(例如，语音提示功能)的实际能力。MRFP处理和混合实际的媒体流，MRFC控制MRFP的媒体流资源。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 其他问题-在设计和标准化UMTS的过程中，产生了很多复杂的问题。例如，在2000年底才确定下来一个用户的服务控制由它的归属网络来执行，并且，当用户漫游到国外网络时，这个功能仍然适用，但是，因为存在仅仅由归属域控制产生的潜在的劣势，例如，归属域的过载和处理分组上的延迟，所以由访问域进行控制的问题也已经开始考虑了。而且，关于支持由访问域和归属域通过IMS共同控制的问题，3GPP已经讨论了一段时间了。然而支持两种模式必定会使网络结构更加复杂。因此，3GPP最终决定使用归属域来控制，但是，以后可能会重新进行这一问题的讨论。 IMS 3. IMS - 应用 3.1即时通 (Push to talk) 又叫做一键通业务，该服务使得手机终端用户能够在分组交换网络上，通过只按一个按键就进行一对一或群体即时通话。该服务采取 “ 半双工 ” 模式，也就是说同一时间只有一人能够讲话，从而更便于群体交流，a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 该服务可以使用户能够在通话群中灵活地选定或者变换通话对象。从而用户可以轻易地与通话群体中所有人或选择部分人进行 Push to talk 通话。它是一种全数字传输的 VoIP 技术，其完全基于 SIP协议和IMS的设计，很好的保证了互通性、可量测性和向未来 3G 的平滑过渡。 3.2 IP电话业务 随着宽带IP接入的普及，IP终端电话成为新的热点，例如现在一些运营商正在推广的IP超市(类似于IP公用电话亭)，基于 H.323 的IP终端电话未能普及除了以前缺乏IP宽带接入这个原因外，还因为 H.323 的用户认证一直是一个问题，另外H.323终端价格昂贵也是一个原因。现在采用SIP基本上克服了这些问题，SIP软件被免费集成在 Microsoft WinXP 操作系统中，因为SIP如此简单，甚至有运行在 Linux ， PocketPc ，Symbian 上的 SIP Client软件，使得手持终端上的SIP应用也成为可能，而且SIP还支持完善的用户认证机制。所以基于Sa fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel IP的IMS完全可以被用来作为IP终端电话系统。 3(3 串行振铃和并行振铃业务 因为一个SIP用户可以同时在很多终端上注册，比如他可能有几个固定办公电话，还有无绳电话，移动电话，便携PC等，每种终端可以实现不同的功能，比如便携PC支持视频而固定SIP电话可能连P&M都不支持，用户不需要总是带着所有终端，在各种情况下他只带着其中一些，比如开会时他可能只带着便携PC。 串行振铃业务是当另外一个用户呼叫该用户时，系统会根据该用户设定的次序和等待时间依次振铃该用户的各种终端，直到该用户接通为止。 而并行振铃业务则是系统同时振铃该用户的所有注册终端，直到该用户接通为止。 3.4 会晤转移业务 会晤转移业务包括无条件转移，无应答转移和遇忙转移，该用户可以定制转移的统一资源标识(URI)，当条件符合时，呼叫被转移到设定的目标。这种业务和传统电话呼叫转a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 移业务功能相同，只是增加了新的媒体类型。 3.5 主叫标识显示业务 和传统电话的主叫号码显示意义相同，只不过显示在被叫终端上的不只是主叫的SIPURI，而可能是任何媒体，比如一张主叫的照片、一段声音或者视频片断。根据系统的提示，主叫可以事先将要传送的标识上传到系统中存储，当主叫呼叫被叫时，SIP消息报文将主叫标识的统一资源地址(URL)传到被叫，被叫终端自动打开该URL，从而看到主叫的标识。 IMS 4.IMS - 安全问题分析 IP多媒体子系统(IMS)是3GPP在R5规范中提出的，旨在建立一个与接入无关、基于开放的SIP/IP协议及支持多种多媒体业务类型的平台来提供丰富的业务。它将蜂窝移动通信网络技术、传统固定网络技术和互联网技术有机结合起来，为未来的基于全IP网络多媒体应用提供了一个通用的业务智能平台，也为未来网络发展过程中的网络融a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 合提供了技术基础。IMS的诸多特点使得其一经提出就成为业界的研究热点，是业界普遍认同的解决未来网络融合的理想方案和发展方向，但对于IMS将来如何提供统一的业务平台实现全业务运营，IMS的标准化及安全等问题仍需要进一步的研究和探讨。 4.1 IMS存在的安全问题分析 传统的电信网络采用独立的信令网来完成呼叫的建立、路由和控制等过程，信令网的安全能够保证网络的安全。而且传输采用时分复用(TDM)的专线，用户之间采用面向连接的通道进行通信，避免了来自其他终端用户的各种窃听和攻击。 而IMS网络与互联网相连接，基于IP协议和开放的网络架构可以将语音、数据、多媒体等多种不同业务，通过采用多种不同的接入方式来共享业务平台，增加了网络的灵活性和终端之间的互通性，不同的运营商可以有效快速地开展和提供各种业务。由于IMS是建立在IP基础上，使得IMS的安全性要求比传统运营商在独立网络上运营要高的a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 多，不管是由移动接入还是固定接入，IMS的安全问题都不容忽视。 IMS的安全威胁主要来自于几个方面:未经授权地访问敏感数据以破坏机密性;未经授权地篡改敏感数据以破坏完整性;干扰或滥用网络业务导致拒绝服务或降低系统可用性;用户或网络否认已完成的操作;未经授权地接入业务等。主要涉及到IMS的接入安全(3GPP TS33.203)，包括用户和网络认证及保护IMS终端和网络间的业务;以及IMS的网络安全(3GPP TS33.210)，处理属于同一运营商或不同运营商网络节点之间的业务保护。除此之外，还对用户终端设备和通用集成电路卡/IP多媒体业务身份识别模块(UICC/ISIM)安全构成威胁。 4.2 IMS安全体系 IMS系统安全的主要应对措施是IP安全协议(IPSec)，通过IPSec提供了接入安全保护，使用IPSec来完成网络域内部的实体和网络域之间的安全保护。3GPP IMS实质上是叠加在原有核心网分组域上的网络，对PS域没有太大的依赖性，在PS域中，业务的a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 提供需要移动设备和移动网络之间建立一个安全联盟(SA)后才能完成。对于IMS系统，多媒体用户也需要与IMS网络之间先建立一个独立的SA之后才能接入多媒体业务。 3GPP终端的核心是通用集成电路卡(UICC)，它包含多个逻辑应用，主要有用户识别模块(SIM)、UMTS用户业务识别模块(USIM)和ISIM。ISIM中包含了IMS系统用户终端在系统中进行操作的一系列参数(如身份识别、用户授权和终端设置数据等)，而且存储了共享密钥和相应的AKA(Authenticati on and Key Agreement)算法。其中，保存在UICC上的用户侧的IMS认证密钥和认证功能可以独立于PS域的认证密钥和认证功能，也可和PS使用相同的认证密钥和认证功能。IMS的安全体系如图1所示。 图1 IMS安全体系结构图 图1中显示了5个不同的安全联盟用以满足IMS系统中不同的需求，分别用?、?、?、?、?来加以标识。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel ?提供终端用户和IMS网络之间的相互认证。 ?在UE和P-CSCF之间提供一个安全链接(Link)和一个安全联盟(SA)，用以保护Gm接口，同时提供数据源认证。 ?在网络域内为Cx接口提供安全。 ?为不同网络之间的SIP节点提供安全，并且这个安全联盟只适用于代理呼叫会话控制功能(P-CSCF)位于拜访网络(VN)时。 ?为同一网络内部的SIP节点提供安全，并且这个安全联盟同样适用于P-CSCF位于归属网络(HN)时。 除上述接口之外，IMS中还存在其他的接口，在上图中未完整标识出来，这些接口位于安全域内或是位于不同的安全域之间。这些接口(除了Gm接口之外)的保护都受IMS网络安全保护。 SIP信令的保密性和完整性是以逐跳的方式提供的，它包括一个复杂的安全体系，要求每个代理对消息进行解密。SIP现在使用两种安全协议:传输层安全协议(TLS)和IPSec，TLS可以实现认证、完整性和机密性，a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 用TLS来保证安全的请求必须使用可靠的传输层协议，如传输控制协议(TCP)或流控制传输协议(SCTP);IPSec通过在IP层对SIP消息提供安全来实现认证、完整性和机密性，它同时支持TCP和用户数据报协议(UDP)。在IMS核心网中，可通过NDS/IP来完成对网络中SIP信令的保护;而第一跳，即UE和P-CSCF间的信令保护则需要附加的测量，在3GPP TS 33.203中有具体描述。 4.3 IMS的接入安全 IMS用户终端(UE)接入到IMS核心网需经一系列认证和密钥协商过程，具体而言，UE用户签约信息存储在归属网络的HSS中，且对外部实体保密。当用户发起注册请求时，查询呼叫会话控制功能(I-CSCF)将为请求用户分配一个服务呼叫会话控制功能(S-CSCF)，用户的签约信息将通过Cx接口从HSS下载到S-CSCF中。当用户发起接入IMS请求时，该S-CSCF将通过对请求内容与用户签约信息进行比较，以决定用户是否被允许继续请求。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 在IMS接入安全中，IPSec封装安全净荷(ESP)将在IP层为UE和P-CSCF间所有SIP信令提供机密性保护，对于呼叫会话控制功能(CSCF)之间和CSCF和HSS之间的加密可以通过安全网关(SEG)来实现。同时，IMS还采用IPSec ESP为UE和P-CSCF间所有SIP信令提供完整性保护，保护IP层的所有SIP信令，以传输模式提供完整性保护机制。 在完成注册鉴权之后，UE和P-CSCF之间同时建立两对单向的SA，这些SA由TCP和UDP共享。其中一对用于UE端口为客户端、P-CSCF端口作为服务器端的业务流，另一对用于UE端口为服务器、P-CSCF端口作为客户端的业务流。用两对SA可以允许终端和P-CSCF使用UDP在另一个端口上接收某个请求的响应，而不是使用发送请求的那个端口。同时，终端和P-CSCF之间使用TCP连接，在收到请求的同一个TCP连接上发送响应;而且通过建立SA实现在IMS AKA提供的共享密钥以及指明在保护方法的一系列参数上达成一致。SA的管理涉及到两个数据库，即内部和外部数据库(SPD和SAD)。Sa fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel PD包含所有入站和出站业务流在主机或安全网关上进行分类的策略。SAD是所有激活SA与相关参数的容器。SPD使用一系列选择器将业务流映射到特定的SA，这些选择器包括IP层和上层(如TCP和UDP)协议的字段值。 与此同时，为了保护SIP代理的身份和网络运营商的网络运作内部细节，可通过选择网络隐藏机制来隐藏其网络内部拓扑，归属网络中的所有I-CSCF将共享一个加密和解密密钥。 在通用移动通信系统(UMTS)中相互认证机制称为UMTS AKA，在AKA过程中采用双向鉴权以防止未经授权的“非法”用户接入网络，以及未经授权的“非法”网络为用户提供服务。AKA协议是一种挑战响应协议，包含用户鉴权五元参数组的挑战由AUC在归属层发起而发送到服务网络。 UMTS系统中AKA协议，其相同的概念和原理被IMS系统重用，我们称之为IMS AKA。AKA实现了ISIM和AUC之间的相互认证，并建设了一对加密和完整性密钥。用来认证用户a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 的身份是私有的身份(IMPI)，HSS和ISIM共享一个与IMPI相关联的长期密钥。当网络发起一个包含RAND和AUTN的认证请求时，ISIM对AUTN进行验证，从而对网络本身的真实性进行验证。每个终端也为每一轮认证过程维护一个序列号，如果ISIM到超出了序列号码范围之外的认证请求，那么它就放弃该认证并向网络返回一个同步失败消息，其中包含了正确的序列号码。 为了响应网络的认证请求，ISIM将密钥应用于随机挑战(RAND)，从而产生一个认证响应(RES)。网络对RES进行验证以认证ISIM。此时，UE和网络已经成功地完成了相互认证，并且生成了一对会话密钥:加密密钥(CK)和完整性密钥(IK)用以两个实体之间通信的安全保护。 4.4 IMS的网络安全 在第二代移动通信系统中，由于在核心网中缺乏标准的安全解决方案，使得安全问题尤为突出。虽然在无线接入过程中，移动用户终端和基站之间通常可由加密来保护，但是在核心网时，系统的节点之间却是以明文来a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 传送业务流，这就让攻击者有机可乘，接入到这些媒体的攻击者可以轻而易举对整个通信过程进行窃听。 针对2G系统中的安全缺陷，第三代移动通信系统中采用NDS对核心网中的所有IP数据业务流进行保护。可以为通信服务提供保密性、数据完整性、认证和防止重放攻击，同时通过应用在IPSec中的密码安全机制和协议安全机制来解决安全问题。 在NDS中有几个重要的概念，它们分别是安全域(Security Domains)、安全网关(SEG)。 4.4.1 安全域 NDS中最核心的概念是安全域，安全域是一个由单独的管理机构管理运营的网络。在同一安全域内采用统一的安全策略来管理，因此同一安全域内部的安全等级和安全服务通常是相同的。大多情况下，一个安全域直接对应着一个运营商的核心网，不过，一个运营商也可以运营多个安全域，每个安全域都是该运营商整个核心网络中的一个子集。在NDS/IP中，不同的安全域之间的接口定a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 义为Za接口，同一个安全域内部的不同实体之间的安全接口则定义为Zb接口。其中Za接口为必选接口，Zb接口为可选接口。两种接口主要完成的功能是提供数据的认证和完整性、机密性保护。 4.4.2 安全网关 SEG位于IP安全域的边界处，是保护安全域之间的边界。业务流通过一个SEG进入和离开安全域，SEG被用来处理通过Za接口的通信，将业务流通过隧道传送到已定义好的一组其他安全域。这称为轮轴-辐条(hub-and-spoke)模型，它为不同安全域之间提供逐跳的安全保护。SEG负责在不同安全域之间传送业务流时实施安全策略，也可以包括分组过滤或者防火墙等的功能。IMS核心网中的所有业务流都是通过SEG进行传送，每个安全域可以有一个或多个SEG，网络运营商可以设置多个SEG以避免某独立点出现故障或失败。当所保护的IMS业务流跨越不同安全域时，NDS/IP必须提供相应的机密性、数据完整性和认证。 4.4.3 基于IP的网络域安全体系[2] a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel NDS/IP体系结构最基本的思想就是提供上从一跳到下一跳的安全，逐跳的安全也简化了内部和面向其他外部安全域分离的安全策略的操作。 在NDS/IP中只有SEG负责与其他安全域中的实体间进行直接通信。两个SEG之间的业务被采用隧道模式下的IPSec ESP安全联盟进行保护，安全网关之间的网络连接通过使用IKE来建立和维护[3]。网络实体(NE)能够面向某个安全网关或相同安全域的其他安全实体，建立维护所需的ESP安全联盟。所有来自不同安全域的网络实体的NDS/IP业务通过安全网关被路由，它将面向最终目标被提供逐跳的安全保护[5]。其网络域安全体系结构如图2所示。 图2 基于IP的网络域安全体系 4.4.4 密钥管理和分配机制[5] 每个SEG负责建立和维护与其对等SEG之间的IPSec SA。这些SA使用因特网密钥交换(IKE)协议进行协商，其中的认证使用保存在SEG中的长期有效的密钥来完成。每个a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 对等连接的两个SA都是由SEG维护的:一个SA用于入向的业务流，另一个用于出向的业务流。另外，SEG还维护了一个单独的因特网安全联盟和密钥管理协议(ISAKMP)SA，这个SA与密钥管理有关，用于构建实际的对等主机之间的IPSec SA。对于ISAKMP SA而言，一个关键的前提就是这两个对等实体必须都已经通过认证。在NDS/IP中，认证是基于预先共享的密钥。 NDS/IP中用于加密、数据完整性保护和认证的安全协议是隧道模式的IPSec ESP。在隧道模式的ESP中，包括IP头的完整的IP数据包被封装到ESP分组中。对于三重DES加密(3DES)算法是强制使用的，而对于数据完整性和认证，MD5和SHA-1都可以使用。 4.4.5 IPSec安全体系中的几个重要组成和概念[5] 1)IPSec:IPSec在IP层(包括IPv4和IPv6)提供了多种安全服务，从而为上层协议提供保护。IPSec一般用来保护主机和安全网关之间的通信安全，提供相应的安全服务。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 2)ISAKMP:ISAKMP用来对SA和相关参数进行协商、建立、修改和删除。它定义了SA对等认证的创建和管理过程以及包格式，还有用于密钥产生的技术，它还包括缓解某些威胁的机制。 3)IKE:IKE是一种密钥交换协议，和ISAKMP一起，为SA协商认证密钥材料。IKE可以使用两种模式来建立第一阶段ISAKMP SA，即主模式和侵略性模式。两种模式均使用短暂的Diffie-Hellman密钥交换算法来生成ISAKMP SA的密钥材料。 4)ESP:ESP用来在IPv4和IPv6中提供安全服务。它可以单独使用或与AH一起使用，可提供机密性(如加密)或完整性(如认证)或同时提供两种功能。ESP可以工作在传送模式或隧道模式。在传送模式中，ESP头插入到IP数据报中IP头后面、所有上层协议头前面的位置;而在隧道模式中，它位于所封装的IP数据报之前。 标准化组织对IMS的安全体系和机制做了相应规定，其中UE和P-CSCF之间的安全由接入网络安全机制提供，IMS网络之上的安全a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel 由IP网络的安全机制保证，UE与IMS的承载层分组网络安全仍由原来的承载层安全机制支持。所有IP网络端到端安全基于IPSec，密钥管理基于IKE协议。对于移动终端接入IMS之前已经进行了相应的鉴权，所以安全性更高一些。但是对于固定终端来说，由于固定接入不存在类似移动网络空中接口的鉴权，P-CSCF将直接暴露给所有固定终端，这使P-CSCF更易受到攻击。为此，在IMS的接入安全方面有待于进一步的研究，需要不断完善IMS的安全机制。 a fine of 100 Yuan. 7.5.3 accident penalties (1) injuries fatalities directly punished 1~2 million. Direct responsibility for the accident and have the corresponding responsibility of leadership, such as concerning administrative sanctions, should be brought to the company or the relevant Department. (2) personal injury accident occurred, the direct punishment 0.5-10,000 yuan, responsible for the direct responsibility for the accident and the responsibility of leadership, such as concerning administrative sanctions should be dealt with by the personnel Department of the company. (3) personal injury accident occurs, the direct punishment 500-1000, who is directly responsible for the accident responsibility, give notice of criticism and 50-100 economic sanctions against them. (4) to conceal the accident, reported without undue delay or false, to inform the administrative leadership of the criticism, resulting in serious consequences, the pursuit of leadership, along with 500-1000 punishment. (5) significant near miss should be attempted as the case of responsible for the accident and construction team injuries accident penalty provisions, mutatis mutandis. Eight, should perform in the construction standards and specifications, serial number a 1 GB3323-2005 steel fusion welded butt joints, welding engineering-Ray lighting and quality rating of 2 GB11345-89 steel welds manual methods of ultrasonic inspection and testing results for grade 3 GB50236-2002 industrial pipe welding engineering code for construction and acceptance of field equipment 4 HGJ222-92 technical specification for welding of aluminium and its alloys 5 low temperature steel welding procedure 6 SH3525-2004 petrochemical JB/ T4708-2000 of welding procedure qualification for steel pressure vessels 7 JB/4709-2000 8 JB4730-2005 pressure vessel