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List of terms
Nortel Multiservice Switch 7400/15000/20000
Terminology
NN10600-005 7.2S1 Standard
PCR7.2 and up March 2006
Copyright © 2006, Nortel Nortel Confidential
availability-bit signaling
The availability-bit (A-bit) signaling technique exchanges availability status
between the two ends of a frame relay permanent virtual channel (PVC)
connection. A-bit signaling permits each end of a PVC to determine if the
remote end is ready to process data.
availability message packet (AMP)
An availability message packet (AMP) is a status message sent by a hunt
group member to its hunt group server. A hunt group member sends an AMP
each time its availability status changes significantly.
available bit rate (ABR)
An ATM service category. ABR permits dynamic allocation of bandwidth to
applications that are highly tolerant of cell delay and delay variance, such as
LAN interconnection. ABR traffic is characterized as very bursty.
available cell rate (ACR)
The available capacity of an ATM link. In general, ACR refers to links that are
already in use by one or more ATM connections.
B-channel
See bearer channel (B-channel) (page 19).
B-ICI
See broadband inter-s interface (B-ICI) (page 21).
B3ZS
See binary 3 zero substitution (B3ZS) (page 19).
B8ZS
See binary 8 zero substitution (B8ZS) (page 19).
backbone
A group of interconnected core nodes that normally tandem traffic. A
backbone node exchanges full topology information with all nodes in the same
topology region that are not cluster nodes. The backbone exchanges limited
routing and no topology information with clusters. The backbone does not
exchange any information with nodes in other topology regions.
backbone border node
Nortel Multiservice Switch nodes that reside on a backbone boundary,
connected by backbone-cluster border links to cluster nodes.
backbone node
Nortel Multiservice Switch nodes that reside within a backbone.