Nortel Networks NN43001-563 - Manual (Page 25)

IP Trunk 3.01 (and later) and CS 1000M 25
2. Gatekeeper Confirm (GCF) – From the Gatekeeper to the Active
Leader, with the functional Gatekeeper IP address. This address is used
for all call control messaging and registration messages between the IP
Trunk 3.01 (and later) cards and the Gatekeeper.
3. Gatekeeper Registration Request (RRQ) – From the Active Leader to
the Gatekeeper, with all of the node’s IP addresses.
IP addresses are only sent if required. A CS 1000M does not require all
IP addresses, so the IP addresses are not sent.
4. Gatekeeper Register Confirm (RCF) – From the Gatekeeper to the
Active Leader, providing the TTL prior to a re-registration attempt by
the leader and indicating under what conditions admission requests
are needed.
Typically, the TTL is in minutes. The default IP Trunk 3.01 (and later)
value, if no response from the Gatekeeper is received, is 300 seconds.
However, the Gatekeeper can enforce a shorter interval in seconds or
tens of seconds. The standards allow seconds from 1 to (232) –1.
Recommendation
Nortel recommends that the TTL be provisioned in the 30- to 60-second
range.
The IP Trunk 3.01 (and later) node must perform a "keep-alive"
re-registration prior to the expiry of the timer on the Gatekeeper. When
the Gatekeeper timer expires, a full registration is needed.
IP Trunk 3.01 (and later) and CS 1000M
The CS 1000M systems use virtual trunking (IP Peer Networking) to
inter-operate with the IP Trunk 3.01 (and later) nodes. However, the CS
1000M can be a Gatekeeper for the system.
When IP Trunk 3.01 (and later) is part of a network with a Signaling Server
acting as a central control point, it is able to take partial advantage of a
feature known as IP Peer Networking. IP Peer Networking eliminates the
multiple conversions between IP and non-IP circuits, increasing call routing
efficiency and overall voice quality. Many calls involving an IP Peer endpoint
and one or more IP Trunk endpoints can use this capability. However, calls
that use only IP Trunk facilities, and a small subset of calls involving both
IP Trunk and IP Peer, cannot obtain this benefit.
IP Trunk 3.01 (and later) supports Gatekeeper Registration and Admission
Signaling (RAS) and Call Admission Signaling. IP Trunk 3.01 (and later)
interworks with CS 1000M, which fulfills the role of a Gatekeeper. Using
H.323 RAS, IP Trunk 3.01 (and later) uses RAS Messaging to register
with the Gatekeeper if provisioned to do so. IP Trunk 3.01 (and later) then
processes calls by scanning its Directory Number (DN) information. If the
Nortel Communication Server 1000
IP Trunk Fundamentals
NN43001-563 01.01 Standard
Release 5.0 30 May 2007
Copyright © 2007, Nortel Networks
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