Operation Manual

Glossary
SIP Software Release 6-0-0
J613-M0524-00
113
NVS Nonvolatile Storage. Static RAM that has its contents preserved through
gateway power cycles through the use of a battery that maintains power to
the RAM.
O
octet An octet is 8 bits. This term is used in networking, rather than
byte,because some systems have bytes that are not 8 bits long.
OSI Open Systems Interconnection. A suite of protocols, specifically ISO
standards, to be the international standard computer network architecture.
See ISO.
P
packet The unit of data sent across a network. “Packet” is a generic term
used to describe units of data at all levels of the protocol stack, but it is most
correctly used to describe application data units. See datagram, frame.
packet switching A communications paradigm in which packets
(messages) are individually routed between hosts, with no previously
established communication path.
parity A method of checking the integrity of characters transmitted serially.
It does this by defining an extra bit whose value is set to ensure either an
even (even parity) or odd (odd parity) number of ‘1’ bits in the character.
patch A piece of computer code used to correct or enhance an existing piece
of code. In the router, patches are applied by “overlying” them on existing
code in RAM. The patches are loaded into the router using a process called
downline loading.
PBX Private Branch Exchange (1) An automatic or manual private telephone
exchange for transmission of calls to and from the public telephone network.
(2) A switching system located on a customerʹs premises that consolidates
the number of inside lines (extensions) into a smaller number of outside
lines (trunks). Many PBXs also provide advanced voice and data
communication features.
ping Packet InterNet Groper. A program used to test reachability of
destinations by sending them an ICMP echo request and waiting for a reply.
The term is used as a verb: “Ping host X to see if it is up!”.
POTS Plain Old Telephone System. Standard telephone service used by most
residential locations; basic service supplying standard single line telephones,
telephone lines, and access to the public switched network.
privilege A term used in computing to refer the access rights or level of
trusted afforded to a user of the computer system. A privileged user has
access to “more powerful” commands which may (adversely) affect the