Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations strongm on being selected by the Tek-Tips community for having the most helpful posts in the forums last week. Way to Go!

Echo cancellation

Status
Not open for further replies.

1148tr

MIS
Mar 15, 2007
53
US
We have recently switched to (Paetec) MPLS for our data network and one voice PRI is being handed off the MPLS router. We have an S8500 with two G650 gateways with the one MPLS PRI, as well as one standard PRI and copper trunks for backup and before the the install of the MPLS network we never had echo but now we seem to have echo on the MPLS PRI, the standard PRI and even on the copper trunks. We were told nothing changed on the standard PRI or the copper lines. All the phones are 2400 series digital sets. We have turned on echo cancellation on the trunk groups and on the DS1 boards but we still have occational echo, usually during the begining of the call. The DS1's are set to EC 4. Is there a setting to help with echo at the beginning of a call or should we try at different echo cancellation setting? Any suggestion would be greatly appreciated. Thanks.
 
here is an AVAYA white paper on echo, and echo cancellation:
ftp://ftp.avaya.com/incoming/Up1cku9/tsoweb/definity/Echo_Management_ATM-IP_System.pdf

You are more likely to get echo with a VoIP PRI, than a traditional PRI, because of the delays introduced via the IP network.

In my experience, no good comes out of VoIP IP trunks, none, zip, nada, zilch. despite what anyone claims or tells you, there is nothing better than a PRI from a CLEC delivered over copper pairs. Your fake MPLS VoIP PRI is also highly compressed and bandwidth starved.

Call Paetec, see what they suggest. You'll probably end up back on the circuit switched PRI. I do realize everyone wants to save money, but if you can't hear the person your calling, is it really worth it?

BTW, on the newer TN464HP cards, there are more echo cancellation settings that can be tried. You also enabled echo cancellation on the DS1 form as well, I assume?

mitch


AVAYA Certified Specialist
 
Mitch,

Thanks. We have contacted Paetec and they keep telling us it is a problem on our PBX. We have turned on echo cancellation on the DS1 board and tried adjusting the EC setting...the echo only happens occationally. The real problem at this point seems to be that Paetec is somehow routing occational DID calls down our copper trunks which have an incoming destination to the attendant...when she gets these calls she always hears echo. Therefore Paetec is so set on blaming the PBX for the echo since as they see it we have echo on the PRI as well as the copper trunks. DID calls should not be coming in over the copper trunks. We are waiting to see if Paetec and determine why some DID calls are coming in over the copper trunks - not an overflow issue since the PRI is not being over utilized. Thakns again.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top