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Problem with SIP trunk to Avaya Office System


Does anyone have any experience with interconnecting a UC520 with Avaya office telephony?

We have attempted to get a SIP trunk working in either direction and I can get the SIP headers/diagnostics with 'term mon' and 'debug ccsip all'. however I cant work out why we are sending a 500 error reply back to the Avaya setup.



Community Member

Re: Problem with SIP trunk to Avaya Office System

Hi Chris,

Interesting one this request

500 error at this stage (And it is just an educated guess) is that the Avaya system is not authenticating to the UC properly, you may need to investigate the registration process a little.

Also if you are setting this up as a SIP-UA trunk then I am going to go out on a limb here and say that it wont work... been there, tried it and spent days working on this with an Avaya tech and refuse to embark on it again

You will need to setup a Global DN registration which is for SIP end points, and to do this you would need to know your way around the CLI, I can provide to you a sample configuration if you would like, and this would get it to work if done correctly, but you do have some reduced functionality.

Otherwise as a last resort you could setup a H.323 trunk which would work and that is how the UC500 does its site-2-site setup any way (Which really doesn't make sense when SIP would be better).

Let us know how you are trying to do this so we can try and map out the best way to do it.

OH and i forgot to mention the following: This will not be a support configuration by Cisco Support, if you want Cisco support you would need to be UC express certified and have the support registered for Cisco TAC (CLI Configuration) and not SBS Support which is CCA only... That's my disclaimer done with

Good luck...



Cheers, David Trad. **When you rate a persons post, you are indicating a thank you or that it helped, but at the same time you are also helping to maintain the community spirit - You don't have to rate posts and you wont be looked down upon :) *
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