Some telecommunication terms compiled from the Internet

PSTN Public exchange telephone network refers to a collection of all circuit exchange telephone networks, namely, fixed telephone networks, providing a considerable part of the Internet's long-distance infrastructure.

Psdn public exchange digital network.

ISDN generally refers to the N-ISDN, that is, Integrated Service Digital Network, can provide a speed of kbps. It allows users to call and access the Internet at the same time. Generally, the telephone line is analog, while ISDN is digital. It provides two channels, called B channel, with each channel providing a rate of 64 Kbps. When both the Internet and the phone are connected, the two channels are used for communication and Internet access. When no phone call is made, the two channels are used for Internet access, and the call rate reaches kbps.

The ADSL Asymmetric Digital user line uses a common telephone line as the transmission medium. The uplink traffic is 640 Kbps and the downlink traffic is 8 Mbps.

B-ISDN broadband ISDN, whose core is ATM technology.

The circuit exchange establishes a dedicated line connection between the two communication points until the line is released after the information transmission is complete.
Group switches group information during communication, store and forward each group, and dynamically select a path through routing.
The packet exchange uses the packet as a complete transmission unit and transmits the packet according to the route as in group exchange. It is a very old transmission method, which is used in telegraph networks and so on. Due to different message lengths, the buffer allocation is complicated.

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Plmn public land mobile communication network, divided into local plmn (lplmn) and roaming plmn (vplmn ). For example, China Mobile and China Unicom are two plmn instances.

 
BSc broadwidth serve Controller Broadband Service Control Center

BTS base transceiver station receiving and sending station

BSS Base Station Subsystem, including a BSc and several BCS.

Imsi International Mobile User identification code, stored in SIM card. The total length cannot exceed 15 digits. Among them, 3 bits are MCC, and China is 460; MNC is a mobile network number, up to 2 bits are used to identify mobile communication networks, such as China Mobile and China

China Unicom, etc.; msin is a mobile user identification code.

IMEI international mobile device code, with a total length of 15 characters, can be queried by entering "* #06.