I'm trying to better understand how CUC is integrated in an SME environment. The design is a centralised SME cluster with CUCM leaf clusters in 3 regions. All 3 leaf clusters are to share a 20K user CUC cluster. The CUC is to have a SIP integration.
Is it the case that the CUC cluster still needs to be integrated with the 3 leaf clusters as one would normally do, i.e. create 3 telephony integrations in CUC and assign a SIP port group to each with the SME being used only for the call routing i.e. a SIP trunk pointing to the CUC cluster?