CUCM 12.5 on CLOUD

[Rima]

Hello Team,

Is It possible de deploy CUCM 12.5 on the cloud and configure an intercluster trunk between this CUCM and a CUCM v11.5 on-premise?

Thank you.

[TechLvr]

I think your best bet in this scenario is to use a CUBE to integrate the two clusters. You can put this on-Orem CUBE behind NAT (recommended) or give it a give a public IP, and create a SIP trunk from your cloud CUCM to the CUBE over TLS. The SIP trunk between your on-prem CUCM and the CUBE does not have to use TLS. This would be a secure solution. 

If you decide to create intercluster trunks directly between the cloud and on-prem CUCM clusters without a CUBE, you have to put your CUCM and your phone subnets behind NAT. You would also need a firewall that does SIP ALG, or STUN/TURN servers to relay media. Even if you get this setup to work, it is not secure at all, and I am not even sure if Cisco supports this. 

[b.winter]

That's not a question in regards to the CUCM's.
You have to answer the question of basic IP connectivity between the CUCM's.

[Roger Kallberg]

The only cloud option for CM is to use what is know by Dedicated Instance in the Cisco cloud. To that you can stand up a trunk. How that is done depends on the connectivity option that you have in-place for the connection to the Cisco cloud service. You cannot install CM on other cloud hosting services, such as AWS or Azure to name a few.