[cisco-voip] QSIG over H323 with GK

[James Brown]

Thank you Nick. I'm not sure about changing the service parameter to 
ECMA because we'd like to use Inter Cluster Trunking at some point. 
According the the System Guide, UCM 6.1 "does not support ECMA with QSIG 
tunneling over intercluster trunks". Since this is a global parameter, I 
guess we'd have to leave it on ISO. Would this prevent basic calls 
connecting, or does it just affect the supplementary features, like CLI?

Regards

James.

Nick Matthews wrote:
> A few notes:
> 
> -CUCM has an advanced service parameter to switch between ISO/EMCA.
> It would be for every QSIG link.
> -GK should only be relevant to routing calls, which for QSIG purposes
> should be basic H323.
> 
> H323 is the best choice for this since it's based off of Q.931 and
> you'll see less 'conversion' of parameters.
> 
> 
> 
> -nick
> 
> On Thu, Apr 23, 2009 at 6:54 PM, James Brown
> <james.m.h.brown at googlemail.com> wrote:
>> All,
>>
>> We have an opportunity to convert some existing QSIG E1 tie-lines (between
>> TDM PBXs) to IP and at the same time allow our UCM cluster to reach the PBX
>> sites. I wondered if anyone could spare a few minutes to advise me on the
>> implementation please?
>>
>> My preferred setup would be:
>>
>> UCM H225 Trunk <--> GK <--> H323 IOS GW <--> TDM PBX
>>
>> The reason I like H323 in this instance is that this environment includes
>> four separate PBXs and I'd like to keep the old dial-plan away from UCM and
>> use GK CAC. The PBXs are various Nortel models and I believe the IOS H323
>> implementation may offer slightly more flexibility when integrating.
>>
>> Having read around the topic, it seems that UCM supports ISO QSIG whereas
>> IOS supports ECMA QSIG. To make matters worse, UCM tunnels QSIG over H323
>> using Annex M, while IOS uses the GTD field within a GKTMP message.
>>
>> Could anyone tell me whether a Cisco GK could successfully reconcile what
>> looks like a different versions of QSIG and different tunnelling mechanisms
>> please? Is the approach I'm taking valid, or would I be better using MGCP?
>> Does anyone have any experiences they could share when integrating with a
>> Nortel Option 61/81 with QSIG?
>>
>> Many thanks,
>>
>> James.
>>
>> _______________________________________________
>> cisco-voip mailing list
>> cisco-voip at puck.nether.net
>> https://puck.nether.net/mailman/listinfo/cisco-voip
>>