建立对Asterisk和FreeSWITCH电话交换机分布式电话应用

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Introduction VoIP (Voice Over Internet Protocol) is the umbrella of protocols used to transmit voice (or video) over data networks. Mixing data and voice, or considering voice as data in a special format, opened the door for applications that were not available in the pure PSTN (Public Switched Telephone Network). Nowadays, most VoIP switches are computer based, with Linux as the operating system of choice. Although there are plenty of available open-source VoIP switches, ASTERSIK was for a long time the de-facto switch for open-source low density switches. Another late-comer is FreeSwitch, which has learned from ASTERSIK and was build as a high capacity, well designed Soft-Switch. ADM Telephony Server (ATS) makes use of ASTERISK and FreeSwitch to offer a distributed application server. Why ADM Telephony Server (ATS) Although both switches (ASTERISK and FreeSwitch) offer an API to develop call management applica