Chapter 3 Building the Network

3.9.1 Discovering NEs

3.9.1 Discovering NEs

The network discovery service in CTM collects information from individual NEs, discovers new NEs added to the network, and computes network-level information, such as physical topology and discrepancies.

When you add a new NE to CTM, the discovery process starts. When the process finishes, all of the NE information (such as inventory, configuration, physical topology, and discrepancies) is collected and CTM is updated.

3.10How Do I Synchronize the Network for Optical and Routing Devices?

Use the NE Explorer to synchronize the CTC-based NEs in your network. The following sections describe the synchronization settings in detail.

3.10.1Synchronization Settings for the ONS 15310, ONS 15327, ONS 15454 SONET, and ONS 15600 SONET

Full Cisco IOS configuration synchronization is performed automatically by CTM to keep the NE and the CTM Data Provisioning Service synchronized. Full configuration resynchronization might be delayed depending on the usage of the CTM server.

For more information, see Chapter 7, “Provisioning Services and Connections.”

Synchronization status messaging (SSM) is a SONET protocol that communicates information about the quality of the timing source. SSM messages are carried on the S1 byte of the SONET Line layer. These messages enable SONET devices to automatically select the highest quality timing reference and to avoid timing loops.

SSM messages are either Generation 1 or Generation 2. Generation 1 is the first and most widely deployed SSM message set. Generation 2 is a newer version. If SSM is enabled, consult the timing reference documentation to determine which message set to use. Table 3-18and Table 3-19show the Generation 1 and Generation 2 message sets.

 

 

Table 3-18

SSM Generation 1 Message Set

 

 

 

 

 

 

 

 

 

Message

Quality

 

Description

 

 

 

 

 

 

 

 

 

PRS

1

 

Primary reference source—Stratum 1

 

 

 

 

 

 

 

 

 

STU

2

 

Synchronization traceability unknown

 

 

 

 

 

 

 

 

 

ST2

3

 

Stratum 2

 

 

 

 

 

 

 

 

 

ST3

4

 

Stratum 3

 

 

 

 

 

 

 

 

 

SMC

5

 

SONET minimum clock

 

 

 

 

 

 

 

 

 

ST4

6

 

Stratum 4

 

 

 

 

 

 

 

 

 

DUS

7

 

Do not use for timing synchronization

 

 

 

 

 

 

 

 

 

RES

 

Reserved; quality level set by user

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Cisco Transport Manager Release 6.0 User Guide

 

 

 

 

 

 

 

 

 

78-16845-01

 

 

 

 

 

 

3-55

 

 

 

 

 

 

 

 

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Cisco Systems 78-16845-01 manual Discovering NEs, Message Quality Description