3.1 APS Overview
The APS immediately switches services from a faulty link to a normal link by switching and
recovering linear multiplex sections.
3.1.1 APS Overview
The Automatic Protection Switching (APS) protocol uses the Multiplex Section Overhead
(MSOH) to transmit signals. APS works in either 1+1 or 1:N mode.
APS Principle
APS is an important feature of a Synchronous Digital Hierarchy (SDH) network. APS uses a
protect link to protect traffic on one or more working links. If a working link fails, services on
the working link automatically switches to the protect link, preventing data loss and improving
network reliability.
shows an SDH network is a supporting network and allows the establishment of
large-scale data communications networks with high bandwidth. For example, data networks A
and B can communicate with each other by multiplexing services to SDH payloads and
transmitting the payloads over fibers. An APS-enabled router can protect traffic on a link to an
Add/Drop Multiplex (ADM) or a Radio Network Controller (RNC) of an SDH network that has
APS functions. Two APS-enabled routers can also protect traffic on direct links between them.
HUAWEI NetEngine80E/40E Router
Configuration Guide - Reliability
3 APS Configuration
Issue 02 (2014-09-30)
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