IP trunk card description 43Card combinationsThe Leader and DCHIP, or Follower and DCHIP, functions can reside on asingle IP trunk card or multiple IP trunk cards. If a Follower card is equippedwith a DCH PC card, it can function as a DCHIP trunk card. As an IP Trunk3.01 (and later) node becomes larger with more trunk traffic, load balancingshould be configured. When load balancing is required, the Leader andDCHIP functionality are placed on separate cards which are assignedthe least call traffic. For the largest IP Trunk 3.01 (and later) nodes andnetworks, the Leader and DCHIP cards can be partially configured withtrunk ports or have no trunk ports at all.An example configuration that allows for redundancy and backup is thefollowing:• Card 1: Leader and DCHIP #1• Card 2: Backup Leader and DCHIP #2• Card 3: Follower #1 – 24 trunks connected with DCHIP #1• Card 4: Follower #2 – 24 trunks connected with DCHIP #2To support more trunks, more DCHs can be added. Each DCHIP card cansupport a maximum of 15 NT0961AA ITG-Pentium 24-Port Follower cardsor 11 NTVQ90BA Media Card 32-port Follower cards. This limit is due tothe maximum limit of 382 trunks in an ISL route.Each DCHIP card controls a separate group of Follower cards. If a DCHIPcard fails, its associated Followers are removed from service as well. Forvery large nodes, it is recommended that Follower cards be spread acrossmultiple DCHIPs, in order to provide some resiliency by allowing the IP Trunk3.01 (and later) node to continue handling calls when one DCHIP card fails.A DCHIP card and all of the IP trunk cards connected with it belong to oneLeader card. This means that the cards also belong to a single customer.The group of IP trunk cards connected with one Leader is referred to as anIP Trunk 3.01 (and later) node. If a single Meridian 1/CS 1000M systemhas multiple customers requiring IP Trunk 3.01 (and later) connectivity,a separate IP Trunk 3.01 (and later) node is required for each customer.Multiple DCHIPs can be configured for each node.All DCHIPs in an IP Trunk 3.01 (and later) node must be configured with thesame DCH protocol. If the user wants to use multiple DCH protocols, theuser must configure multiple IP Trunk 3.01 (and later) nodes.Nortel Communication Server 1000IP Trunk FundamentalsNN43001-563 02.01 StandardRelease 5.5 21 December 2007Copyright © 2007, Nortel Networks.
