Digium, Inc.
Page 68
Appendix C Glossary and Acronyms
PTT
Post, Telegraph, and Telephone
The government agencies in many countries that traditionally operated
and monopolized the public postal, telegraph, and telephone services.
QoS
Quality of Service
A set of quality requirements for telephone service.
RBOC
Regional Bell Operating Companies
The creation of Regional Bell Operating Companies were a result of
AT&T's telephone monopoly being broken up in 1983.
REN
Ringer Equivalence Number
An arbitrary value which denotes the electrical load a telephone ringer has
on a line.
RJ11
A six-pin jack typically used for connecting telephones, modems, and fax
machines in residential and business settings to PBX or the local
telephone CO.
SIP
Session Initiation Protocol
An IETF standard for setting up sessions between one or more clients. It
is currently the leading signaling protocol for VoIP, gradually replacing
H.323.
