CUCM SIP Normalization Script for incoming NOTIFY

[Waldo Roca Martin]

Hi

I have a new deployment in a costumer that wants to connect to VoIP Internet Service provider for outgoing calls. This is trunk is connecting directly in CUCM (no CUBE involve)

The problem is on the firewall that it doesn't change the URI domain from Public IP to CUCM Internal IP when apply NAT for incoming calls. The Ing in charge have no much Idea to enable this, so CUCM refuse the call.

Meanwhile firewall guy try to figure out to fix this. I'm thinking to try modify the URI to use a script normalization in trunk but I am not sure if I am able to do this. 

can Sip normalization script be applied on Incoming Notify from in CUCM Trunk? I know in cube you can not, but for CUCM I don't know.

Thank you

Best Regards.

[Mohammed al Baqari]

Hi,

I don't think this will work. LUA scripting can definitely modify notify message but you need first to accept the call before applying the script assigned to the SIP trunk. If CUCM is rejecting the message then LUA script won't be applied. CUCM needs to accept the message to apply LUA scripting. 

Firewalls won't be able to modify URI in SIP headers since they aren't made for this. Can't you deploy CUBE to resolve this. This is why CUBE is always recommended to connect to ITSPs for hiding IP addressing and the call flow working.

[Waldo Roca Martin]

Hi

Thanks for your answer.

We get a 404 not found from CUCM. We have the correct translations rule and CSS for the DDI number. For that reason we think it is a URI problem and because in the Request-URI we get the Public IP.

I though CUBE can not modify the incoming NOTIFY also. And it was a Firewall responsibility.

Anyway we have not CUBE available for this.

We appreciate any advice to resolve this.

Thank you

Best regards

[Ayodeji Okanlawon]

If the host portion of the URI doesn't contain the IP address of any of your CUCM servers, then CUCM cant accept the call. You will have to configure your NAT properly such that when the request is sent to CUCM, it has the correct host address in the RURI. There is no magic to it. Perhaps you want to open a thread in security section of the forum on how to properly configure your Firewall

[Waldo Roca Martin]

Thanks for the answer.

Yea your right. Just to be sure there is something I could do.

The firewall is checkpoint.

Ok I will insist to the firewall guy to try to fix it.

Thank you