Integrate Cube with MS Teams Design

[eng.eslamany]

I have a customer which has E1 cards for incoming and outgoing calls and we needs to configure integration with MS Teams using the below link Direct Routing for Microsoft Phone System with Cisco Unified Border Element (CUBE)

the CUBE has one interface only pointing to CUCM

can we use the same interface or do we need another interface?

[Scott Leport · Accepted solution]

Hi,

You can use the same interface, but you will need a static NAT entry to be configured on your firewall / Internet gateway to map the private IP to a public IP. The public IP also needs to be unique as you'll need to create DNS records for the CUBE and that will also be required when you obtain the necessary certificates from your CA too. 

You would also follow the "CUBE behind NAT" sections of the doc when completing your configuration. 

[TechLvr · Accepted solution]

Single interface should work fine if you want to do NAT as Scott pointed out. You also need some outbound SIP profiles on your CUBE to modify your private IP to your Public IP in the SIP SDP headers. 

Alternatively, you can use sub-interfaces on your CUBE. Refer to the diagram below (IP addresses are not real).
You need to consult with your network and firewall teams to ensure this is acceptable.

[Khurram Tariq]

Hi @eng.eslamany 

Good day

can you provide me your show run because i am also implementing the same scenerio for our customer, it would be helpful