Nortel Networks SRG50 - Manual (Page 98)

98 Glossary
NN40140-500 NN40140-500
main office, main
office call server The system that provides telephony services to redirected SRG IP telephones in
normal mode.
NCS Network Connection Server
The NCS is an H.323 gatekeeper. It provides standard H.323 gatekeeper functionality,
as well as support for branch office and virtual office features.
normal mode
The operating mode of the SRG when connectivity with the main office is
established.
QoS Quality of Service
In IP telephony, QoS refers to the quality of the voice communication channel. There
are inherent difficulties associated with transmitting voice over IP and quality of
service is a significant challenge for service providers. QoS specifications allow
service providers and their customers to establish and monitor acceptable levels of
service.
SIP An IP gateway protocol used by both the main office and the SRG to create VoIP
trunking connections.
steering codes Steering codes are similar to line pool access codes and destination codes. Steering
codes determine where a call gets routed.
TPS (Internet Telephone) Terminal Proxy Server
A TPS controls the connection between IP telephones.
UDP Uniform Dialing Plan
Each location within the network is assigned a Location Code. On a private network,
this code precedes the directory number of the telephone being dialed. Depending on
routing configuration, this number may be part of the destination code, or it may
automatically be dialed out when the appropriate destination code is dialed before the
directory number. Under the Uniform Dialing Plan (UDP), the SRG must include this
code in the BUID.
UDP User Datagram Protocol
A member of the TCP/IP protocol suite that transports data as a connectionless
protocol, using packet switching. Generally, ports on the SRG support UDP.
VoIP trunk Voice over IP trunk
A pathway between two systems that allows voice to be transmitted over an IP
connection.
WAN Wide Area Network
A computer network that spans a relatively large geographical area. The largest WAN
in existence is the Internet.
ZDP Zone Digit Prefix
The main office appends this number to an SRG local-PSTN call dialed from an SRG
IP telephone. The number differentiates the call from a main office local-PSTN call
dialed by a main office telephone.