Alcatel-Lucent 7710 SR SONET, Configuration Manual

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Interface Configuration
7710 SR OS Interface Configuration Guide Page 33
• Several Alcatel-Lucent Media Dependent Adapters (MDAs) support channelization down
to the DS-0 level. ATM, Frame Relay, PPP, and cHDLC are supported encapsulations on
channelized ports.
• Link Aggregation (LAG) — LAG can be used to group up to 16 ports into one logical
link. The aggregation of multiple physical links allows for load sharing and offers
seamless redundancy. If one of the links fails, traffic will be redistributed over the
remaining links. Up to 16 links can be supported in a single LAG, up to 200 LAGs can be
configured on a node.
• Multilink Bundles — A multilink bundle is a collection of channels on channelized ports
that physically reside on the same MDA. Multilink bundles are used by providers who
offer either bandwidth-on-demand services or fractional bandwidth services (fraction of a
DS-3/E-3 for example). Multilink bundles are supported over PPP channels (MLPPP) and
ATM channels (IMA).
• APS — Automatic Protection Switching (APS) is a means to provide redundancy on
SONET equipment to guard against linear unidirectional or bidirectional failures. The
network elements (NEs) in a SONET/SDH network constantly monitor the health of the
network. When a failure is detected, the network proceeds through a coordinated
predefined sequence of steps to transfer (or switchover) live traffic to the backup facility
(called protection facility.) This is done very quickly to minimize lost traffic. Traffic
remains on the protection facility until the primary facility (called working facility) fault
is cleared, at which time the traffic may optionally be reverted to the working facility.
• Bundle Protection Group (BPGrp) — A BPGrp is a collection of two bundles created on
the APS Group port. Working bundle resides on the working circuit of the APS group,
while protection bundle resides on the protection circuit of the APS group. APS protocol
running on the circuits of the APS Group port monitors the health of the SONET/SDH
line and based on it or administrative action moves user traffic from one bundle to another
in the group as part of an APS switch.
Note: TDM ports are not supported on 7210 SAS-X