“SS7 is the protocol stack that governs call signaling and
billing on the public switched telephone network (PSTN). SS7 is
used by carriers as a common language for communicating call-routes
and bandwidth consumption in the never-sleeping international
telephone network…“And an army of willing accomplices are already laying the
groundwork, developing tomorrow’s telephony systems. One of them is
Digium, which makes hardware and software that lets you turn your
Linux PC into a fully-functional soft-based voice switching
system–like that elaborate, fridge-sized PBX at the office, only
much smaller and cheaper. Digium’s softPBX, which is open-source,
is called Asterisk…”
Related Story:
NewsForge:
Open Source Helps Power SIP Phone Popularity(Aug 02, 2004)