铁通-网通-联通-移动-电信的区别（CRC - China Netcom - China Unicom - Mobile Telecommunications difference）

铁通-网通-联通-移动-电信的区别（CRC - China Netcom - China Unicom - Mobile Telecommunications difference） 铁通-网通-联通-移动-电信的区别(CRC - China Netcom - China Unicom - Mobile Telecommunications difference) The difference between the 1, China Mobile, China Telecom, China Unicom, China Netcom, Chinese China Chinese ctt: China Mobile, China Telecom, China Unicom, China Netcom, China China Chinese Tietong that five companies in 2008 before the reorganization of the telecommunications industry, China Mobile and China Unicom Chinese mainly engaged in mobile services (GSM, CDMA mobile phone business), China Telecom, China Netcom, Tietong business Chinese China fixed network business (fixed telephone, broadband). In 2008 after the re combination, become a wholly owned subsidiary of Tietong mobile (mobile, mobile CTT + = new) mainly engaged in fixed network +2G (GSM) +3G (TD-SCDMA); Chinese Unicom and Netcom merged into the United China network company (Unicom Netcom + = new Unicom) mainly engaged in fixed network +2G (GSM) +3G (WCDMA); The acquisition of the former Telecom China Unicom's CDMA network, the China Telecom mainly engaged in fixed network +2G (CDMA) +3G (CDMA2000). At present, the three operators in the 2G business is China Mobile's strengths, fixed network business of China Mobile is the worst. Fixed network business China Telecom is strong, but in the mobile business is the worst. Chinese Unicom's business is more balanced than the telecom fixed network business is a bit poor, but the mobile telecommunications business is strong, in the mobile business (2G) than mobile, but fixed network business than the mobile strong. (fixed network business ranked second, mobile service (2G) is second) in 3G Unicom with WCDMA this card, I believe we can make a difference. 2 China Unicom advantage Chinese Unicom's CDMA network advantage is very outstanding, this is a very good development opportunity of China unicom.. Chinese Unicom logo is the only warm, I really love this color. Our replacement with many successful cases, such as Lenovo standard after development is very successful. Each enterprise has reason for the subject, change back to a series of strategic initiatives. Change is a good starting point, but can not succeed, but also depends on since then the company has taken a series of marketing, management and marketing strategy. But after all, from the senses to attract users is only a start, Unicom to impress users from the emotion, but also the need for a series of marketing activities, increase the user experience of the relevant business. Brand driven to have at least six elements, including fees, services, channels, incentives, feedback and so on, these elements together, and the collision of user groups, users can understand the connotation of the brand from the emotional. China Unicom is the first step for the subject, made a good start, the future is still a long way. Now China Unicom after a series of personnel changes, Guangzhou city user growth is very fast, either profit or income have been greatly improved. From the market point of view, Chinese Unicom vice president Li Gang took office after the great movement, now vice president Li Gang mentioned the most, is the development and transformation of the problem is, from the original pure investment type enterprises change to the scale and efficiency of enterprises. Now China Unicom in promoting the fine marketing work at the same time, also to promote the integration of business. Professor Ceng Jianqiu of Beijing University of Posts and Telecommunications China Unicom since its inception to today, especially from 1999 to now, the development of such a scale in such a short period of time, the speed of its development and market share in the global view is extraordinary. Chinese Unicom is the only one with C and G two network operators, this is the unique advantage of China unicom. But in C, China Unicom G two network advantages and management, including performance management, precise marketing, personnel and other aspects should also be further strengthened. D? Development, there are more places can deepen. 13, what's the problem inside you must answer "of course. You have to prepare through your questions, more information about the company, the interview, the job. Here are some questions for you to choose: 1, why is this job to open recruitment? 2, the company (the Department) what is the biggest challenge? 3, the company's long-term goals and strategic plan you can use one or two words to briefly introduce for me? 4, do you consider this position to serve people should have what qualities? How long will the 5 decide to hire roughly time period? 6, about my qualifications and abilities, what do you want to ask? 7. what is the company training plan for the employment of college graduates, pay attention to whether their occupation development plan? ATM is Asynchronous Transfer Mode (ATM) for asynchronous transfer mode ATM is a data transmission technology is one of the core technologies of B-ISDN service. ATM is a packet switching and multiplexing technique in cell based, it is a variety of business in order to design a universal connection oriented transmission mode. It is suitable for LAN and WAN, it has high data transmission rate and communication in many types such as voice, data, fax, video, audio and image quality CD support. CDMA is the use of spread-spectrum communication technology, which can reduce the interference between the mobile phone, and can increase the user capacity, and mobile phone power could be very low, it can not only make use of time longer, the more important is that it can reduce the electromagnetic wave of radiation damage. The bandwidth of CDMA can be extended greatly, and images can be transmitted, this is the reason why the third generation mobile phone CDMA. Safety performance, CDMA has excellent authentication system for the transmission properties, a code to distinguish between users, to prevent being stolen greatly enhanced the ability to listen to. The CDMA system was developed rapidly. Wideband CDMA (WCDMA) wideband CDMA transmission technology, an important basis for the technology of IMT-2000, will be one of the standard of the third generation digital wireless communication system. WCDMA is Wideband Code Division Multiple English Access (wideband code division multiple access) the English referred to, is a third generation wireless communication technology. W-CDMAWideband CDMA is a specifically formulated by 3GPP, GSM MAP UTRAN (UMTS core network based on terrestrial radio access network) for the wireless interface of the third generation mobile communication system. At present, WCDMA Release 99, Release 4, Release 5, Release 6 version. At present, Chinese used the Unicom 3G communication standard. 2.6 what is the baseband transmission? What is the frequency band transmission? What kinds of modulation methods in band transmission? Answer: the original digital data in 0 or 1 in the form of wholly intact in channel transmission, called baseband transmission. Is the first band transmission baseband signal (modulation) to the analog signal transmission in the analog channel in high frequency range (called band signal), then the frequency band signal transmission in the analog channel. In band transmission according to the control parameters of the modulated carrier is different, there are three kinds of modulation: amplitude shift keying, frequency shift keying and phase shift keying. 2.9 what is the multiplex? There are several commonly used multiplexing technology, try the? Answer: multiplexing is to many signal transmission in a single channel and technology. The multiplexing system can be combined with information from multiple information sources, and then the synthetic information group by a single transmission line and transmission equipment. Multiplexing technology commonly used mainly has four forms: frequency division multiplexing (Frequency Division Multiplexing, FDM), time division multiplexing (Time Division Multiplexing, TDM), wavelength division multiplexing (Wavelength Division Multiplexing, WDM) and code division multiplexing (Code Division Multiplexing, CDM). 2.10 in the computer network, the way of data exchange are there? What are the advantages and disadvantages? Answer: the data after encoding in communication transmission line according to the data transmission technology division, exchange network can be divided into a circuit switched network, packet switching network and packet switching network. (1): the first set of circuit switching a complete path must be prior to data transmission. On line removal (release) before the pathway by a pair of users fully occupied. The circuit switching efficiency is not high. (2): message exchange message from source to destination by way of transfer storage and forwarding the message queue. So the message exchange is not suitable for interactive communication, can not meet the requirement of real-time communication. (3): packet switched packet switching and packet switching is similar, but the message is divided into packets, and specifies the maximum length. Packet switching is a switching technology in data network is the most widely used, suitable for medium or large amounts of data exchange. 2.11 ATM switching characteristics? Answer: the ATM switch has the advantages of circuit switching and packet switching, switching delay is small, flexible access rate, high channel utilization. It supports constant bit rate (cell cycle appears) continuous operations, and support (cell cycle appears non burst) business; support and support business operation in low speed, high speed, but also can support the transmission (cell density different) business, supports both real-time and non real time business support services. Therefore, the ATM exchange is to realize the broadband integrated services digital network (B-ISDN) is a kind of good broadband switching technology. 6.8 what is the ADSL? ADSL what are the characteristics? Answer: ADSL (Asymmetrical Digital Subscriber Line, asymmetric digital subscriber line) is a method of using twisted pair high-speed data transmission technology. ADSL can provide 3 channels in the ordinary telephone line, the lowest band part is 0KHz-4KHz, for ordinary telephone service, part of the 20KHz-50KHz middle frequency band, used to transmit uplink data information, the highest frequency band is 150KHz-550KHz or 140KHz-1.1MHz, for transmitting downlink data. That is to say, the use of ADSL in the existing telephone line can access Internet, you can call and send a fax, phone and Internet access do not affect each other. Therefore, ADSL can make full use of the existing telephone network, only need to provide high-speed broadband access for users to install ADSL devices on both ends of the line. 7.5 what is the subnet? What does it do? Answer: the subnet mask is used to determine whether the IP address belongs to a subnet. For example, a host in the LAN to send IP packet, Baotou carries through the destination IP address, subnet mask, you can determine a packet is sent to the host within the network, or sent to the network host, in order to choose different treatment. Subnet mask form: network and subnet address part of the 1, the formation of the 0 host IP address 7.11 what is the DNS domain name system? What does it do? Answer: in order not to have to remember the IP address those hard to remember, through meaningful words to memory network address, appeared the domain name system (DNS Domain, Name System). The function of DNS, simply said, is through the name of the database will host names into IP addresses. Can also be reversed, the upcoming IP address to host name. 44, SSL (Secure Sockets Layer secure socket layer), and its successor, the transport layer security (Transport Layer Security, TLS) is a security protocol to provide security and data integrity for network communication. TLS and SSL in transport layer network connection encryption. China Mobile, China Telecom, China Unicom, China Netcom, China China Chinese Tietong that five companies in 2008 before the reorganization of the telecommunications industry, China Mobile and China Unicom Chinese mainly engaged in mobile services (GSM, CDMA mobile phone business), China Telecom, China Netcom, Tietong business Chinese China fixed network business (fixed telephone, broadband). In 2008 after the re combination, become a wholly owned subsidiary of Tietong mobile (mobile, mobile CTT + = new) mainly engaged in fixed network +2G (GSM) +3G (TD-SCDMA); Chinese Unicom and Netcom merged into the United China network company (Unicom Netcom + = new Unicom) mainly engaged in fixed network +2G (GSM) +3G (WCDMA); The acquisition of the former Telecom China Unicom's CDMA network, the China Telecom mainly engaged in fixed network +2G (CDMA) +3G (CDMA2000). At present, the three operators in the 2G business is China Mobile's strengths, fixed network business of China Mobile is the worst. Fixed network business China Telecom is strong, but in the mobile business is the worst. Chinese Unicom's business is more balanced than the telecom fixed network business is a bit poor, but the mobile telecommunications business is strong, in the mobile business (2G) than mobile, but fixed network business than the mobile strong. (fixed network business ranked second, mobile service (2G) is second) in 3G Unicom with WCDMA this card, I believe we can make a difference. The third generation mobile communication technology (3rd-generation, 3G), refers to the cellular mobile communication technology to support high-speed data transmission. The 3G service can transmit voice and data information at the same time, the rate of general in more than a few hundred kbps. At present, there are four kinds of 3G standards: CDMA2000, WCDMA, TD-SCDMA, WiMAX. "The two generation of GSM, CDMA and other digital mobile phone (2G), the third generation mobile phone (3G) generally refers to a new generation of mobile communication system with wireless communication and Internet multimedia communication, 3G will and community website future combination, the combination of WAP and web is a kind of trend, such as the popular micro blogging website: Sina micro-blog, Weibo has already joined this application. The main difference between 3G and 2G is the voice and data transmission speed of the upgrade, it can achieve better wireless roaming in the global scope, and image processing, music, video and other forms of media, including web browsing, telephone conference, e-commerce and other information services, also want to consider the good compatibility with the existing second generation systems. In order to provide this service, the wireless network must be able to support different transmission speeds, that can support at least 2Mbps respectively in the indoor and outdoor and Vehicular Environments (megabits), 384kbps (kbit / s) and the transmission speed of 144kbps (this value according to the network environment will change). 3G is the third generation communication network, currently supporting ITU to determine the three wireless interface standard, namely China Telecom CDMA2000, Chinese Unicom WCDMA, China Mobile TD-SCDMA, GSM equipment is used in TDMA, and CDMA code spread spectrum technology, advanced power and voice activation can provide at least 3 times greater than GSM network capacity, the industry will be CDMA technology as the mainstream technology of 3G, ITU determined three wireless interface standard, which is the United States CDMA2000, European WCDMA, TD-SCDMA Chinese. The original China Unicom CDMA now sold to China Telecom, China Telecom CDMA has been upgraded to 3G network, 3G is able to provide the main features of mobile broadband multimedia services. The first generation of the 1995 advent of the analog mobile phone (1G) can only make voice calls; 1996 to 1997 of the second generation of GSM, CDMA and other digital mobile phone (2G) will increase the function of the received data, such as receiving email or web page; in fact, 3G is not born in 2009, has produced 3G in early 2002 abroad but, China also developed in 2003 China 3G, but in 2009 it was formally listed. Peak downlink speeds of up to 3.6Mbit/s theory (say 2.8Mbit/s), the peak uplink speed up to 384kbit/s. Don't be like the Internet that 2G per second, of course, a movie can not be completed instantly. Note: G3 is not 3G, but the abbreviation of "Guide3", Guide has two layers of meaning, the verb represents lead, influence, control and other means, the noun represents leader, the meaning of the wizard.