Cisco ASR 900 Series Configuration Guide

Configuring ACR and DCR for SAToP
Configuring ACR for SAToP
Adaptive Clock Recovery (ACR) is an averaging process that negates the effect of random packet delay
variation and captures the average rate of transmission of the original bit stream. ACR recovers the original
clock for a synchronous data stream from the actual payload of the data stream. In other words, a synchronous
clock is derived from an asynchronous packet stream. ACR is a technique where the clock from the TDM
domain is mapped through the packet domain, but is commonly used for SAToP.
To configure E1 ACR:
enable
configure terminal
controller sdh 0/4/0
rate STM1
no ais-shut
alarm-report all
clock source internal
overhead s1s0 0
aug mapping au-4
au-4 1
clock source internal
mode tug-3
tug-3 1
mode vc1x
tug-2 1 payload vc12
e1 1 cem-group 1 unframed
e1 1 clock source recovered 1
tug-2 2 payload vc11
tug-2 3 payload vc11
tug-2 4 payload vc11
end
To configure E3 ACR:
enable
configure terminal
controller sdh 0/4/0
rate STM1
no ais-shut
alarm-report all
clock source internal
overhead s1s0 0
aug mapping au-4
au-4 1
clock source internal
mode tug-3
tug-3 1
mode e3
overhead c2 0
cem-group 1 unframed
e3 clock source recovered 1
ACR Global Configuration
enable
configure terminal
recovered-clock 0 4
clock recovered 1 adaptive cem 0 1
end
1-Port OC-192 or 8-Port Low Rate CEM Interface Module Configuration Guide, Cisco IOS XE Everest 16.7.x (Cisco
ASR 900 Series)
107
Configuring SDH on 1-Port OC-192/STM-64 or 8-Port OC-3/12/48/STM-1/-4/-16 Module
Configuring ACR and DCR for SAToP

Cisco ASR 900 Series Specifications

General

Brand	Cisco
Model	ASR 900 Series
Category	Network Router
Language	English