Digium TE800 Series, User Manual, Page: 72 / 75

Appendix C Glossary and Acronyms
PBX Private Branch Exchange
A smaller version of a phone company’s large central switching office.
Example: Asterisk.
PCI peripheral component interconnect
A standard bus used in most computers to connect peripheral devices.
POP Point of Presence
The physical connection point between a network and a telephone
network. A POP is usually a network node serving as the equivalent of a
CO to a network service provider or an interexchange carrier.
POTS Plain Old Telephone Service
The public switched telephone network (PSTN) is the network of the
world's public circuit-switched telephone networks. Originally a network
of fixed-line analog telephone systems, the PSTN is now almost entirely
digital, and now includes mobile as well as fixed telephones.
PPP Point-to-Point Protocol
Type of communications link that connects a single device to another
single device, such as a remote terminal to a host computer.
PRI
Primary Rate ISDN
PSTN Public Switched Telephone Network
A communications network which uses telephones to establish
connections between two points. Also referred to as the dial network.
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