Nortel SRG50, Configuration Manual

Page: 107 / 111

107
Survivable Remote Gateway 50 Configuration Guide
Glossary
BDP Both Dialing Plans.
A dialing plan option that is supported on the main office only. The SRG50 supports
CDP or UDP only. If the main office is running BDP, the SRG50 zone must be
configured to allow either CDP or UDP, not both.
branch office
A system that is remote from the main office but provides telephony services using
the main office servers. When a branch office is a survivable remote gateway,
telephony services are provided by the branch office if communication with the main
office is lost.
call routing Coding that is configured on a system to ensure that outgoing calls are directed to the
correct trunks and incoming calls are directed to the correct device(s) on the system.
(see also: dialing plan)
CDP Coordinated Dialing Plan.
Under the recommended Coordinated Dialing Plan, the Branch User ID can be an
extension (for example, 4567). For more information about CDP, consult the main
office documentation that covers dialing plans.
dialing plan
Each system uses a specific numbering configuration (dialing plan) that determines
how calls will be handled over a private or public network. (see also: call routing)
FXO Foreign eXchange Office: an interface that connects to the PSTN central office and is
the interface offered on a standard telephone. Example: RJ-11 connector that allows
analog connection to the central office.
gatekeeper The gatekeeper is an IP network application that directs IP traffic to all the systems
on the network. Parameters for both the main office and the SRG50 must be assigned
to all gatekeepers on the network. If the gatekeeper is down, the SRG50 attempts to
connect to the alternate gatekeeper, if there is one. If the alternate gatekeeper is also
down, or there is no alternate gatekeeper, the SRG50 IP telephones remain registered
with the main office, but calls cannot be sent to the SRG50.
gateway
The IP portal on each system that establishes the VoIP trunk.
H.323
An IP gateway protocol used by both the main office and the SRG50 to create VoIP
trunking connections.
IP Internet Protocol
IP specifies the format of packets, also called datagrams, and the addressing scheme
in the TCP/IP protocol suite. Where IP defines the packet and addressing scheme,
Transport Control Protocol (TCP) establishes a virtual connection between a
destination and a source.
IP telephones Telephones that can connect directly with a TCP/IP network. Also known as internet
telephones.
local mode
The operating mode of redirected SRG50 IP telephones when connectivity with the
main office is unavailable.
main office, main
office call server The system that provides telephony services to redirected SRG50 IP telephones in
normal mode.