CUCM SIP trunk over VPN

[sxzhang23300]

Can the SIP trunk of CUCM be successfully established through VPN?

The picture below is my preliminary plan.

The requirement is that internal extensions can call each other.
Shanghai, Beijing, and Wuhan go out from their respective voice gateways.
Will there be any problems with this design?

[Nithin Eluvathingal]

You can establish SIP trunk over VPN. . RTP stream will be endpoint to endpoint. so you should configure required route, if not you will endup with the one way or no audio issue.

[Roger Kallberg]

The CM does not know about how the underlying network topology looks like, it’s what is known as network agnostic. As long as the traffic can go reliable from A to B so to say it will work.

[TONY SMITH]

Make sure you have MTU and MSS (if using TCP) set properly.  Some SIP packets can be big and you want these to be correctly fragmented.