Alcatel-Lucent 7710 SR SONET, Руководство по настройке

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Ports
Page 74 7710 SR OS Interface Configuration Guide
APS Applicability, Restrictions and Interactions
Note: The Release Notes document for the relevant SR-OS release should be consulted for details
about APS Restrictions.
APS and Bundles
Bundles (such as IMA and MLPPP) can be protected with APS through the use of Bundle
Protection Groups (bpgrp). For APS-protected bundles, all members of a working bundle must
reside on the working port of an APS group. Similarly all members of a protecting bundle must
reside on the protecting circuit of that APS group.
IMA APS protection is supported only when the router is connected to another piece of equipment
(possibly via an ADM) running a single IMA instance at the far end. By design, the IMA APS
implementation is expected to keep the IMA protocol up as long as the far end device can tolerate
some frame loss. Similarly, the PPP protocol state machine for PPP channels and MLPPP bundles
remains UP when a switchover occurs between the working and protect circuits.
When APS protects IMA groups, IMA control cells, but not user traffic, are sent on the inactive
circuit (as well as the active) to keep the IMA protocol up during an APS switch.
For details on MLFR/FRF.12 support with APS see the section called “MLFR/FRF.12 Support of
APS, BFD, and Mirroring Features”.
Table 22: Supported APS Mode Combinations
Bidirectional 1+1
Signalling APS
Unidirectional 1+1
Signalling APS
Unidirectional 1+1
Signalling and
Datapath APS
Single Chassis APS
(SC-APS) Supported Supported Supported (for 7750
SR-c4/12 platforms
only)
Multi-Chassis APS
(MC-APS) Supported Not supported Not supported