CUCM to sip provider

[west-daniels]

Is it possible to directly connect a CUCM to a sip provider without the use of a gateway?

[Gergely Szabo · Accepted solution]

Hi,

yes, that's possible, although not recommended.

You should use at least a simple firewall. A better option would be to use CUBE.

G.

[west-daniels]

If I do put a firewall in between will there be any issues with NAT

[Gergely Szabo]

Hi,

it depends (on the network topology, among others).

I have seen a customer with a Linux box with a set of iptables rules functioning as a filter between the telco provider and a CUCM cluster.

G.

[west-daniels]

Is it possible to have multiple sip trunks connect to the CUCM to the sip provider 

[Gordon Ross]

SIP Does not work very well (if at all) through a NAT. If you want to NAT the SIP trunk, you really need a session border controller (e.g. CUBE) instead.

GTG

[Jaime Valencia]

Depending on what the telco requires, it might not be feasible without a CUBE in between.