Nortel Networks NN43001-563 Interactions among card functions Active Leader and Follower card interaction

44 System description

Each customer requires one or more dedicated IP Trunk 3.01 (and later)

nodes. Trunks on the same IP Trunk3.01 (and later) node share the same

dialing plan and IP network connectivity. IP Trunk3.01 (and later) trunks

cannot be shared between customers that have independent numbering

plans and IP networks.

It is possible to conﬁgure multiple IP Trunk 3.01 (and later) nodes for one

customer. This conﬁguration allows load balancing among multiple Leaders

for systems with more trafﬁc than a single Leader card can support. The

conﬁguration of multiple IP Trunk3.01 (and later) nodes on one customer

requires splitting the dialing plan among the Leaders. Each Leader must

have a distinct range of the dialing plan. This restriction exists so that a

remote gatewaycan relate a DN with a single IP address.

For information about engineering an IP Trunk3.01 (and later) node, refer to

"ITG engineering guidelines" (page 87).

Interactions among card functionsActive Leader and Follower card interaction

The Active Leader card controls the assignment of IP addresses forall new

ITG-Pentium 24-port and Media Card 32-port trunk cards in its node. If a

new IP trunk card is added as a Follower,the new Card Conﬁguration data,

as programmed in TM 3.1, is downloaded only to the Active Leader card.

When it boots up, the new Followercard requests its IP address from the

Active Leader card through the bootp protocol. When the Follower cards

boot up, they receivetheir IP address and Active Leader card IP address

from the Active Leader card.

Follower cards continuously send Update messages to the Active Leader

card. These messages inform the Active Leader card of the Followers’ most

recent status and resources. The Active Leader sends Update messages

to the Follower cards, informing them of the updated dialing number to IP

address translation information. Also the Active Leader card continuously

sends messages about changes in the network performance of each

destination node in the dialing plan.

If a Follower card fails (for example,DSP failure), it reports to the Active

Leader that its failed resources are not available. The trunk ports involved

are considered faulty and appear busy to the Meridian 1/CS 1000M. Call

processing is maintained on the remaining IP Trunk3.01 (and later) trunks.

If a Follower cardloses communication with the ActiveLeader, all its ports

appear busy to the Meridian 1/CS 1000M. Alarms are raised by sending an

Simple Network Management Protocol (SNMP) trap to the IP addresses

in the SNMP manager list.

Nortel Communication Server 1000

IP TrunkFundamentals

NN43001-563 02.01 Standard

Release 5.5 21 December 2007