Modern building intercom communication network security

Modern building intercom communication network security
 

Buildings Talkback Communicate Radio communication network is a key technology applications and components, development and application of this technology began in the last century 20's, was mainly used in the police headquarters and the patrol Police car Mobile communications services between the car - and quickly used widely in the police department. In 1946, the United States, AT & T Company Developed to design a mobile user can connect the user's mobile telephone and fixed telephone technology; based on this technology, AT & T called the security company to further develop the mobile telephone service (MTS, MobileTelephoneService) mobile communication system security, improve its Type - IMTS system was in 1969 into the only building intercom throughout the U.S. mobile communications network. In 1968, AT & T's Bell Labs invented cellular technology, it would be building intercom mobile communication network coverage area is divided into many similar honeycomb cell, separated by far the district can use the same radio frequency. Cellular technology has greatly increased the capacity of mobile communication networks, and to cell base station to launch a low-power, high transmit power to avoid interference problems caused. Cellular mobile communications in the history of the invention is a glorious milestone, it marks the building intercom extensive use of mobile communications into the cellular mobile communications.
20 century, the late 70s early 80s, the first generation of cellular mobile communication network building intercom in Japan, Sweden, United Kingdom, United States, Germany and France and many other countries, extensive operational. The first generation of cellular mobile communications network based on analog communication technology, using the frequency division multiplexing (FDMA, FrequencyDivision MultipleAccess) mode, the network's capacity to meet the basic needs of mobile users. The 20th century, the late 80s, as the first generation of analog cellular mobile communications network has become obsolete, integrated circuit technology advances in digital communications technology in promoting second-generation cellular mobile communication network security applications. Such as advanced digital voice encoding techniques in the premise of ensuring voice quality can greatly reduce the communication bandwidth needs - to improve network resource utilization band; error control technology enhances the network's anti-jamming capabilities - base station can launch a low-power ; digital encryption technology to protect the users of digital voice, data and Internet instruction; ID technology can be identified mobile user's identity, prevent identity counterfeiting. So the second generation of cellular mobile communications network is not only excellent performance compared to, but Security . 1990, Pan-European digital cellular mobile communication security network (GSM, Global System for MobileCommunication) first began running in Western Europe, for Europe to get rid of the first generation of cellular mobile communication network system, the plight of the many mutually unintelligible. GSM network in the frequency division multiplexing (FDMA) based on another using time division multiple access (FDMA), TimeDivision MultipleAccess) to increase network capacity. Subsequently, Australia, China and some Middle East countries also went with GSM networks, making GSM network coverage of the world's largest mobile communications network.

20 Century 90 on behalf of the end of the building with the Internet and mobile communications network integration, low-rate data transmission services have been unable to meet the needs of mobile users, on the high-speed data transmission needs of driving to the third generation mobile communication networks. To this end, the International Telecommunication Union IT U to promote the development of a globally harmonized building third-generation cellular mobile communication network standards - the future public land mobile telecommunications network. In October 1998 by the European, China, Japan, South Korea and the United States telecommunications standards body jointly set up a record third-generation partnership program (3GPP, the3rd Generation PartnershipProject) organizations, to develop a core network to IS-95 based on the first three generations of mobile communication network standard CDMA2000.

Third generation mobile communication networks floor intercom beginning of this century in use, Japan's DoCoMo Inc. on October 1, 2001 the first third-generation mobile communications network operator

from - news.frbiz.com