McDewey

Note: Cisco bug ID CSCvf28730 is where show sip-ua register status does not reflect the status of SIP trunk registration on a voice class tenant. ILS URI Calls CUBE (Voice Class Route-String) Route Strings are used with CUCM Intercluster Lookup Service (ILS) and can be configured to allow Cisco Gateways to route VoIP calls via the route-string included in the SIP Invite received from a CUCM 9.5+ running the ILS service. This feature was added in Cisco IOS 15.3(3)M and Cisco IOS XE 3.10S. Most ILS connections are CUCM to CUCM and administrators do not bother involving a CUBE for intercluster trunking. However, if you need to perform the function with CUBE in the middle, the options are there. CUCM needs to have the setting Send ILS Learned Destination Route String enabled on the SIP Profile applied to the SIP Trunk in order to send the x-cisco-dest-route-string header to CUBE Full Documentation: Enterprise Application Interoperability for H.323-to-SIP and SIP-to-SIP Configuration Guide, Cisco IOS Release 15M&T Configuration Example CUCM - SIP - CUBE - SIP - CUCM