Ip Telephony - Links

IP Telephony is an umbrella term referring to telephony services provided over the Internet.

Internet Protocol Telephony describes the technologies that use the Internet Protocol's packet-switched connections to exchange voice, fax, and other forms of information that have traditionally been carried over the dedicated circuit-switched connections of the public switched telephone network (PSTN). Using the Internet, calls travel as packets of data on shared lines, avoiding the tolls of the PSTN.

The challenge in IP telephony is to deliver the voice, fax, or video packets in a dependable flow to the user, at a level comparable to that of the PSTN. Much of IP telephony focuses on that challenge.