ip to ip gateway functionality

[fran19422]

Hello I have a CUCM installation that is connected to a 2801 router with CME installed. That 2801 router is then connected to my VOIP provider on the PSTN.

In order to get calls working from my CUCM phones to the outside PSTN and vice versa I understand I need to configure IP to IP gateway functionality in the IOS of my 2801 CME router, i.e enter "voice service voip" mode and then enter "allow-connections sip to  sip".

My question is: is this requirement because I am trying to route CUCM generated SIP calls through a router that already has CME installed and then out to the PSTN ?

i.e. if my 2801 router did not have CME installed then I understand would not need to make any adjustments to the 2801 router i.e the calls would pass through the 2801 router and out to the PSTN without problems ?

Thanks for any comments.

[paolo bevilacqua]

You can have CUBE and CME working at the same time.

[timothy.bailey · Accepted solution]

If you are terminating calls, E1/T1 or SIP onto the 2801 then you will need to configure the router. This is because the authentication will be handed by the router along with the sip connectivity. You will also need to put in the ITSP ip address or DNS into the trusted list for connections. As well as dial-peers to route the calls through to the CUCM.

You may be able to use MGCP on the CUCM but I am not familiar with this.

But yes you should also be able to route the SIP traffic through to CUCM without using any of the 2801's CME capabilities