Has anyone set up Lync server 2010 to use the Gamma SIP trunks, that dont require the use of a gateway?

• No requirement for an additional gateway device, with direct MS Lync connectivity

The trouble is i cannot get Lync to connect to the trunks. We have purchased the SIP trunks from a gamma supplier(we didnt now they were a supplier, until recently when we asked for support and they went 'duhhhhhh me no know, we just sell things dunow how to set things up' what a PAIN IN THE A***), and they say that the SIP trunks are pointed at our EFM IP address. which also has the DDIs assigned to it.

So, i setup a PSTN gateway on lync topology using IP of EFM, Listening port 5060 using TCP. Are these ports and protocol okay?

The VoIP phones seem to want to call, they just lack any sound, no ringing tone, no dissconnected tone. Just says calling "+44157322****" So the dial plan is changing 22**** to the correct local code and whatever the +44 thing is.

Any advice on how i can find the problem, or how to setup the trunks up would be hugely appreciated.

P.S We initially tried to use an audiocodes mediant 1000, which was what we asked our trunk supplier about, and then they informed us about being a gamma supplier, and that the gamma trunks do not require a gateway. Followed setting up guide for mediant 1000 with gamma trunks through audiocodes blah, to no success. I think thats because it was changing the coders, which was not needed if the trunks are directly compatable.

Hi Sorfen,

First , I want you to open the Lync Logging tool and enable it then initiate a call to see what log there.

http://blogs.technet.com/b/nexthop/archive/2012/05/07/troubleshooting-lync-server-2010-with-snooper-part-4.aspx

Also, suggest to look at this Article for how to implement SIP trunk :

http://technet.microsoft.com/en-us/library/gg425743.aspx

 - Most of Trunk provider using Listening to port 5060 using TCP , but you confirm that with them .

 - You need to expose Lync Mediation Server .

and Also , I suggest to ask this Trunk provider what their exact requirements for establish this trunk .

Regards,

Ahmed

Please Mark as Answer if my post help you.

Hi,

Please review the SIP trunk topology.

http://technet.microsoft.com/en-us/library/gg398720.aspx

To  implement SIP trunking, you must route the connection through a Mediation Server, which proxies communications sessions between Lync Server 2010 clients and the service provider and transcodes media when necessary. Each Mediation Server has an internal and an external network interface. The internal interface connects to the Front End Servers. The external interface is commonly called the gateway interface because it has traditionally been used to connect the Mediation Server to a PSTN gateway or an IP-PBX. To implement a SIP trunk, you connect the external interface of the Mediation Server to the external edge component of the ITSP. The external edge component of the ITSP could be a Session Border Controller (SBC), a router, or a gateway.

Generally the gateway is not required in your organization. You need to configure Mediation Server setting. For the details about the SIP trunk configuration of ITSP side, you need to contact Gamme Support for further assistance.

One of the issues i am having is that the FROM and TO header is not set correct, but i am not sure how to do this, and cannot find any articles on changing these. one of the errors i found using the logging tool is:

From: "Chris"<sip:chris@company.co.uk>tag=

To: sip:+44157322xxxx@company.co.uk;tag=

And i think that that should be more along the lines of

From: "Chris"<sip:chris@IP SIP is directed at>

To: sip:+44157322xxxx@88.215.61.195;tag=

88.215.61.195 being the IP of the gamma gateway

Please help me

Hi Sorfen

I am in exactly the same boat as you and have setup some development direct Gamma SIP trunks

Have your reseller spoken to Gamma about Lync setup documentation? This is an email I am just about to write to request through my reseller - if we send this off at the same time and our resellers send this on we might get something out of of big G.

I am loathed to get in a consultant for a day but I fear that may be my best option unless anyone can offer a step by step guide.

Hi SAHurlstone

Sorry for replying so late to this thread, but it might help someone in the future.

With these direct SIP trunks, its so simple to setup its difficult! FE requires 2 NICs, 1 NIC connected to local network, 1 NIC connected to router(or DMZ) and assigned public IP that gamma trunks use. In topology builder, create a new gateway with Gamma IP, gateway listening to TCP 5060, and set FE to listen to TCP 5060, publish topology, create a voice route(local + long distance) that uses gateway. And your done!

The sip trunks require a leading 0 for calls to be successful, so forget about the +44, or 0044 stuff. To test simple create an allow all dial plan (*) and directly dial the number. No manipulations for most calls. Obviously you will wants dial plans to add local area codes and things to save time.

Hope this helps someone!

• Marked as answer by Sorfen Tuesday, January 29, 2013 12:54 PM

Hi Sorfen,

On the 2nd Gamma facing interface on your front end server, did you use an internal IP and NAT it via your firewall, or did you just give your front end server a public IP?

How did you lock down access? Did you use windows firewall?

Give your Front End Server a public IP doesnt sound like a good/supported solution to me?

Thanks

Paul

Hi,

i am wondering if you got this to work. I am using an internal io that is port forwarded from my routers public IP address. Can this work?

also - did you find a way to change the headers?

lastly.. Did gamma provide you with any config documentation?

thanks

jack