MGCP / ISDN Spoofing

[AuditSimon]

We've been let down by our ISDN PRI supplier at a new site, and as a result won't have a PSTN breakout circuit ready when the office goes live in a few days. The MPLS connection for the WAN is up and running, so the gateway can see the Call Manager.

We've put a 2851 Voice Gateway in at the site to provide telephony, but because the PRI circuit isn't working, the gateway isn't registering with Call Manager.

Firstly, is there any way to spoof a PRI circuit on the gateway to get Layer 1 and 2 up so the gateway will register with Call Manager (I've tried "loopback diag" on the interface and this didn't work) ?

Secondly, if the gateway doesn't register with Call Manager, will the phones on the site still register and be able to make internal calls - just not calls onto the PSTN ?

Thanks

 

[mtashiro]

The gateway does not need to be registered in order for the phones to work internally.

As far as making the PRI come up you could try using a T1 Loopback plug but don't really see the point.

 

[pndscm]

I don't think the loopback plug will work on a PRI. The CCM will be looking for D-channel signaling.

 

[DallasBPF]

It might cost a lil on the long distance bill, but you can have them use the home site PRI to make calls outside until the PRI for the building comes up. Its not the 'best' way to do things, but atleast they will be able to make outside calls.

Dallas, Texas
Telecommunications
CCNA, Net+
Working on MCSA, Convergence+, CCVP

 

[iptuser]

You can use a lookback plug as well as issuing DIAG LOOPBACK on the controller I think

 

[whykap]

As pndscm mentioned way above a loopback plug won't do it. It will clear the alarms on the router but won't make it register with ccm. It needs the d-channel up.

I also don't see the point here. If the circuit is not there why does the router need to be registered?
Kind of like buying the helmet and gloves before getting the motorcycle. No point whatsoever.

 

[DallasBPF]

Actually, you can get everything preprogramed and ready to go that way your not rushing the day the circuit is actually installed. All that will need to be done is plugging in the actual PRI. I am actually doing this same scenario with one of our off-sites that is a 2 hour flight from our home office. The only difference is that the circuit is there, just needs be plugged in and the phones are being mailed to them this week. So instead of spending a couple of days there setting it all up on site, I go in and hook up the phones, plug in the PRI, and do some testing.

But to each his own meathod of chaos.

Dallas, Texas
Telecommunications
CCNA, Net+
Working on MCSA, Convergence+, CCVP