The role of the telephone switch - Solutions - Huaqiang Electronic Network

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The telephone switch has four basic call functions. According to the call flow direction of the incoming and outgoing switches and the origin of the originating call, the call can be divided into: local call, outgoing call, incoming call, and transfer call. The switch is understood to be an exchange. A call initiated by the local office can be classified into an outgoing call or a local call according to the flow direction of the call. The calling telephone generates an outgoing call. When the called telephone is another telephone in the local office, that is, the local call is made; the called telephone is not the telephone of the local office, and the switch needs to connect the call to another switch, and an outgoing call is formed. Correspondingly, when an incoming call is sent from another switch, an incoming call is generated when a call is made to the local office; the call is not a call of the local office, and the switch is connected (switched) to another switch, and the switch only provides tandem transit. Function, which forms a transfer call. In addition to the tandem office, which only has the function of "transfer call", each office's telephone switch has the processing capability of these four types of calls. For long-distance and special service calls, it can be seen as a call to a fixed outgoing call.
The telephone exchange is a kind of dedicated switch for telephone exchange within the unit of the industrial and mining enterprises. Its basic function is to complete the mutual communication of the internal telephones of the unit, but it is also equipped with the access network and the network part of the public telephone network. Telephone calls (including local calls, domestic long distance calls and international long distance calls). Since such switches are internal to the unit, a number of additional features can be added depending on the needs of the phone to provide ease of use. Therefore, such switches have greater flexibility. What is a switch?
The telephone exchange is an important part of the local telephone network. It is a supplementary equipment for the local telephone exchange, because it bears a large amount of traffic between the internal telephones of the local telephone network, and reduces the traffic load of the local telephone network. In addition, the telephone exchange is dispersed in each unit and is closer to the telephone, thus shortening the telephone line distance and saving the telephone cable. At the same time, a small number of incoming and outgoing trunks are used to access the local telephone network, which plays a role in traffic concentration. In these respects, the use of telephone switches has greater economic significance. Therefore, in the construction of public networks, the role of telephone switches cannot be lacking.
The technical development trend of telephone exchanges is to adopt telephone telephone exchanges. The new telephone digital subscriber exchange can not only exchange telephone services, but also exchange non-voice services such as data, and realize comprehensive exchange and transmission of multiple services.