No relevant resource is found in the selected language.

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies. Read our privacy policy>Search


To have a better experience, please upgrade your IE browser.

Knowledge Base

FAQ-What Are the Details About the ESC Channel on the OTU (LDGD) in the Intra-Board 1+1 Protection

Publication Date:  2012-07-25  |   Views:  164  |   Downloads:  0  |   Author:  SU1001731839  |   Document ID:  EKB0000403842


Issue Description

In the case of the LDGD board, when you query the DCC state by using command lines or the T2000, only the DCC state of the first optical interface is displayed. (See attachment.)

Alarm Information


Handling Process

Before querying the DCC state of such boards, query the state of the intra-board 1+1 protection group to determine the current working channel.
When you use the T2000 or command lines to query the DCC state, the DCC state of optical interface 1 is actually the DCC state of the current working channel.

Root Cause

The OTU board supporting intra-board 1+1 protection has two optical interfaces on the WDM side. The operation from the optical layer to the electrical layer, however, is actually a selective receiving process because intra-board protection is configured. That is, the ECC information of only one optical interface can be converted into electrical signals and then can be recognized by the SCC board. This optical interface can be optical interface 1 or optical interface 2. To the cm-get-newbdinfo command, the optical interface is regarded as optical interface 1. Hence, in certain cases, even when the fiber at optical interface 1 is removed, the DCC state of optical interface 1 is displayed as OK after the cm-get-newbdinfo command is issued.


If intra-board 1+1 protection is not configured, the services of optical interface 2 cannot be selectively received. Thus, the ESC of optical interface 2 is unavailable.