Lucent Technologies DDM-2000 OC-3 User Manual

363-206-285
Transmission and Synchronization Interfaces
5-52 Issue 3 June 2001
OC-3 and OC-12 5
Figure 5-26 shows how timing can be distributed from an OC-12 line switched ring
to a DDM-2000 OC-3 path switched ring using a dual homing DRI configuration.
The OC-3 DRI nodes are connected via OC-3 point-to-point links terminating in
function unit C slots. The major characteristics of this configuration are:
■ The OC-12 nodes are externally timed
■ The two DDM-2000 OC-3 DRI nodes coordinate timing using
synchronization status messages on the OC-3 ring so that all nodes will
accept timing in the same direction.
■ The two DDM-2000 OC-3 DRI nodes must be provisioned for line timing
with timing derived from function unit C. Synchronization messaging on the
OC-3 span between the two OC-3 DRI nodes must be disabled so timing
loops are not formed. Synchronization messaging and automatic
synchronization reconfiguration should be enabled on all other OC-3
interfaces on the DRI nodes.
■ All other OC-3 nodes must be provisioned for line timing with
synchronization messaging and automatic synchronization reconfiguration
enabled.

Lucent Technologies DDM-2000 OC-3 Specifications

General

Brand	Lucent Technologies
Model	DDM-2000 OC-3
Category	Multiplexer
Language	English