Appendix C: Glossary and Acronyms
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.
RJ45
8P8C, un-keyed modular connector type for Ethernet over twisted pair.
Predominantly used in LAN and uses Unshielded Twisted Pair cable.
RJ48
8P8C modular connector type for T1 and ISDN termination over twisted
pair. While RJ45 and RJ48 use the same connector, they differ in their
wiring. RJ48 is commonly seen on T1 lines and uses Shielded Twisted
Pair cable.
SIP
Session Initiation Protocol
An IETF standard for setting up sessions between one or more clients. It
is currently the leading signaling protocol for Voice over IP, gradually
replacing H.323.
T1
A dedicated digital carrier facility which transmits up to 24 voice
channels (DS0s) and transmits data at 1.544 Mbps. Commonly used to
carry traffic to and from private business networks and ISPs.
T3
A dedicated digital carrier facility which consists of 28 T1 lines and
transmits data at 44.736 Mbps. Equivalent to 672 voice channels (DS0s).
Digium, Inc.
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