Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

CSS in CUCM for H.323 GW with FXS card

I have been working on getting FXS attached devices to be able to make calls (mostly faxing) from a remote site thru our corporate PRI. I have setup the GW in CUCM as H.323 and given it a CSS of "PSTNGateway_CSS" which contains my Internal_PT, VM_Pilot_PT, and Blocked_PT. I have found that I am not able to make outbound calls from FXS connected devices since I do not have any external patterns in those partitions which would be tied to a route list.

My question is:

What is the best practice for H.323 GW configurations in CUCM when you have an FXS card in the router?

Generally, the best practice for a GW is to only give it access to internal patterns (extensions or pilots) so as not to risk toll fraud. However, that is counter productive when you have FXS ports that need to be able to dial the outside world.

H.323 rtr (FXS ports) ----> 50Mb Metro-E ---> CUCM (Corp) ---> H.323 GW (PSTN Access)

As a measure of just making it work, I have added a special partition with local and long distance patterns to the current "PSTNGateway_CSS" so the calls will work.

Cisco Employee

Re: CSS in CUCM for H.323 GW with FXS card

You need to set whatever CSS is required for that GW to make the calls it needs to, whichever it may be in your deployment, otherwise youll be stuck with internal dialing only

Sent from Cisco Technical Support iPad App



if this helps, please rate