CCM 3.3. Mixed ISDN Protocols on Route List

[rbewlay]

When we try to put two Route Groups into the Route List, one with a PRI interface the other with a QSIG interface, it is not allowed. I get the following (which is actually the complete reverse of whats happening):

Note: This route list contains QSIG route groups. The above route group list does not include non-QSIG route groups because you cannot add QSIG and non-QSIG route groups to the same route list.

This is a requirement, because for least cost routing we go via QSIG to the corporate network, then via PSTN for overflow/failure.

Are there any alternatives or a better way of doing this?

[j.ayres]

Unfortunately this is a known restriction with the current Q.Sig implementation in 3.3.

The only workarounds I can think of are:

1) Temporarily switch the PBX to use Q.931 instead of Q.Sig (if it's supported)

2) Use H.323 as the gateway protocol instead of MGCP (of course this isn't an option if you are using 6608s!)

Regards,

Justin

[rbewlay]

Thanks Justin just as I discovered. My only option then seems to be to use PRI or QSIG and an external converter such as the Teltrend series which sucks as a solutution. I'll raise with our Cisco SE.

[d.haeni]

Hi,

Similar to your case, I tried to implement automated rerouting from a QSIG trunk (PBX) to a EURO ISDN trunk (PSTN) on a 6608. My workaround was to configure the PSTN trunk as QSIG; Inbound and outbound calls worked on this trunk, and also did rerouting.

Of course this setup won't be supported by TAC - I'll need to raise with our Cisco SE as well

Hope this helps

cheers,

/David

[rbewlay]

Hmm - yes you can consider QSIG to be a superset of ISDN PRI. Good thinking. Some IEs may just be discarded by the other end running ISDN PRI and be aware of the D-channel usage (contiguous or not) in QSIG.

Thanks

[protzer]

Hi

There is a Cisco internal Feature Request (PER's ID 7510) due to this limitation.

Please, involve the Cisco AM/SE Team to add your business case here.

Thanks,

- Philipp