IM Addressing Scheme Overview
The IM and Presence Service supports two IM addressing schemes:
UserID@Default_Domain is the default IM address scheme when you install the IM and Presence Service.
Directory URI IM address scheme supports multiple domains, alignment with the user's email address, and alignment with Microsoft SIP URI.
You must use the same IM address scheme across all IM and Presence Service clusters.
IM Address Using User@Default_Domain
The default addressing scheme for IM and Presence Service is UserID@Default_Domain.
When you use the UserID@Default_Domain IM address scheme, all IM addresses are part of a single, default IM domain. The default domain value must be consistent across all clusters. Because IM addresses are part of the IM and Presence default domain, multiple domains are not supported.
The UserID can be free-form or synced from LDAP. The following fields are supported:
User Principle Name (UPN)
If you map the UserID to an LDAP field on Cisco Unified Communications Manager, that LDAP mapping must be consistent across all clusters.
Although you can map the UserID to the email address, that does not mean the IM URI equals the email address. Instead it
becomes <email-address>@Default_Domain. For example,
firstname.lastname@example.org@sales-example.com. The Active Directory (AD) mapping setting that you choose is global to all users within that IM and Presence Service cluster.
It is not possible to set different mappings for individual users.
IM Address Using Directory URI
The Directory URI address scheme aligns a user's IM address with their Cisco Unified Communications Manager Directory URI.
The Directory URI IM address scheme provides the following IM addressing features:
Multiple domain support. IM addresses do not need to use a single IM and Presence Service domain.
Alignment with the user's email address. You can configure the Cisco Unified Communications Manager Directory URI to align with a user's email address to provide a consistent identity for email, IM, voice and video communications.
Alignment with Microsoft SIP URI. The Cisco Unified Communications Manager Directory URI can be configured to align with the Microsoft SIP URI to ensure that the user's identity is maintained when migrating from Microsoft OCS/Lync to IM and Presence Service.
If you configure the node to use Directory URI as the IM address scheme, we recommend that you deploy only clients that support Directory URI. Any client that does not support Directory URI will not work if the Directory URI IM address scheme is enabled. Cisco recommends that you use the UserID@Default_Domain IM address scheme and not the Directory URI IM address scheme if you have any deployed clients that do not support Directory URI.
The Directory URI IM address settings are global and apply to all users in the cluster. You cannot set a different Directory URI IM address for individual users in the cluster.
For details on provisioning directory URIs from an external LDAP Directory, see Configure LDAP Directory.
Multiple IM Domains
IM and Presence Service supports IM addressing across multiple IM address domains and automatically lists all domains in the system. You can add, edit, or delete domains. For information on configuring IM domains, see Configure the Domain Overview.
If you are interoperating with Cisco Expressway, see the Cisco Expressway Administrator Guide at http://www.cisco.com/c/en/us/support/unified-communications/expressway-series/products-maintenance-guides-list.html.