ILS between CUCM on different domains

[rchaseling]

Hi,

Have a customer who has an existing on premise Cisco UC enviroment including IMP. They have a bought a Cisco CCE hosted service which will come with its own complete infrastructure including Active Directory, DNS, CUCM, IMP, CCE, PSTN breakout etc. The idea is to keep the two solutions as seperate as possible. There will only be a small number of users who will be Contact Centre agents

The issue is that there is a hard requirement for all agents to use a softphone and as CIPC is going end of support in 3 years we would need to rollout Jabber as the softphone of choice

Mu understanding is that if we enable ILS between the on premise & hosted CUCMs and then create an intercluster peering between the IMP clusters this should work fine as when the agents log into Jabber they will get redirected to the Hosted CUCM & presence etc will all work between them and the rest of the organisation.

My question is - is this possible with different AD domains with no trust? From investigation it appears that this will only work when all clusters are on the same domain

[Jaime Valencia]

If they won't even be in the same domain, then your SRVs will be on each domain and direct the users to either the on-prem on hosted, ILS won't even be involved here.

ILS would be involved if you shared the same domain on both deployments and need to figure out where the user's home cluster is.

On your scenario ILS would enable URI dialing between the cluster, and you would need XMPP federation as inter-cluster peering mandates the same domain on both clusters.

[rchaseling]

Thanks Jaime.

The customer does not want to create a "3rd party" daomin on their network though......so thought I could get around that by configuring ILS.......otherwise agents using Jabber will have to use static config to point to the Hosted CUCM.

I was jsut wondering whether ILS will even work between CUCMs in different domains - I'm going to try and build a lab to test it but thought someone might know off hand

+5 for the the info on XMPP Federation

[Jaime Valencia · Accepted solution]

It works between different domains, you'll exchange the URI information between them and will have call routing once you configure the SIP route pattern and SIP trunk.

[rchaseling]

Many thanks.

Just with all the XMPP federation all the guides show how to configure this via a firewall or Expressway but I assume this will work within the same network provided the _xmpp-server SRV record & relevant A records are available for each domain on the other domains DNS server?

Neither the Hosted solution now the exiting solution have Expressway deployed so I they'll either need to add the hosted domin to their DNS servers (which would also resolve the Jabber auto login) or build Expressway

[rchaseling]

Judt discovered the beauty of Conditonal Forwarders on DNS. Just need to open UDP port 53 between DNS servers and it all works. No ILS, XMPP federation between IP clusters & SIp Intercluster trunk between CUCM clusters