Why This Book

In the late 1990s, I was engineering manager at the switching department in a mobile telecom operator. The mobile switches we dealt with were based on circuit-switched technology. They were big, complex, and proprietary pieces of hardware and software involved almost exclusively in the provision of voice service. By that time, ATM (Asynchronous Transfer Mode), a packet-switched technology that followed the virtual circuit approach, started to gain maturity as a suitable way for carrying media traffic with QoS requirements. Media transport was only part of the problem. The other part, signaling, did not have, by then, a mature candidate. The industry response was to strip the existing circuit switches off their switching matrix ...

Get Internet Multimedia Communications Using SIP now with the O’Reilly learning platform.

O’Reilly members experience live online training, plus books, videos, and digital content from nearly 200 publishers.