<communications> (IPT, Internet Telephony) Use of IP
data connections to exchange voice and fax
data that have traditionally been carried over the public switched telephone network
During the late 1990s, an increasing number of telephone calls have been routed over the Internet
Calls made in this way avoid PSTN charges.
Unlike traditional telephony, IP telephony is relatively unregulated.
Companies providing these services are known as Internet Telephony Service Providers
They include telephone companies, cable TV companies and Internet Service Providers (ISPs).
There are still many problems with voice quality, latency
algorithms, and quality of service
Voice over IP
is an organised effort to standardise IP telephony.
See also Computer Telephone Integration
Internet Telephony Overview (http://www.fokus.gmd.de/research/cc/glone/projects/ipt/).