FOC Testing using ONS15454

exchange1 · ‎06-29-2008

A new FOC is setup to connect our ONS to a far-end optical system (unknown)belonging to another carrier. I want to test the FOC connection for errors, is ONS intelligent to do that?

Tom Randstrom · ‎06-29-2008

Hmmmâ€¦ I think I am followingâ€¦.

Typically, if you wanted to test a circuit you can either, A.) use two test sets, one at each end of the circuit, and insert a test pattern to determine the health of the connection, B.) use a single test set on one end of the circuit, insert a test pattern, and loop-back the far end of the circuit so the signal returns to the test set.

In most cases, a carrier that you are interconnecting with will not allow you to remotely control their terminal equipment, such as with a FEAC (far end activation code). Thus, you would probably need to have the carrier loop back the circuits on their terminal equipment. This type of testing is typical when interconnecting through a third-party carrier.

Doing some research on cisco.com, it looks as though, beginning in R8.5, bit error rate testing (BERT) has been activated on a couple of the 15454 SONET electrical interface cards (See into below). This should allow the user to create a DS-1 circuit, set-up a loopback on the far-end, then have the card insert a DS-1 test pattern and monitor the returned signal for errors. This feature was discussed many years ago but I have not seen its final implementation.

Release 8.5 (Release Notes)

Bit Error Rate Testing

The Bit Error Rate Testing (BERT) feature can be used to test the connectivity, error rate, and error count of the traffic running on an electrical IO card port. The BERT feature is currently supported for Cisco ONS 15454 DS1/E1-56 and DS3XM-12 electrical cards only.

BERT is broadly classified into two components-Test Pattern Generator (TPG) and Test Pattern Monitor (TPM), and is collectively called Test Pattern Generator Monitor (TPGM).

TPGM generates and monitors test patterns like PRBS15, PRBS20, PRBS23, QRSS and ATL1s0s (alternating ones and zeroes). TPGM can inject and monitor errors in the test pattern for both single bit and multirate (1.0E-3, 1.0E-4, 1.0E-5 and 1.0E-6) errors..

Bit Error Rate Testing - Reference Guide

http://www.cisco.com/en/US/docs/optical/15000r8_5/15454/sonet/reference/guide/r85elec.html#wp366408

Hope this helps!

Tom

viyuan700 · ‎07-28-2008

First check a loop from ur ONS.

Then ask the other carrier to give a hard loop from Tx-Rx and check for errors in ur meter if everything is fine there circuit is clean (I am assuming fiber is fine connecting 2 system).