Centralized Deployment Overview
The IM and Presence centralized deployment allows you to deploy your IM and Presence deployment and your telephony deployment in separate clusters. The central IM and Presence cluster handles IM and Presence for the enterprise, while the remote Cisco Unified Communications Manager telephony cluster handles voice and video calls for the enterprise.
The Centralized Deployment option provides the following benefits when compared to standard deployments:
The Centralized Deployment option does not require a 1x1 ratio of telephony clusters to IM and Presence Service clusters–you can scale your IM and Presence deployment and your telephony deployment separately, to the unique needs of each.
Full mesh topology is not required for the IM and Presence Service
Version independent from telephony–your IM andh Presence central cluster can be running a different version than your Cisco Unified Communications Manager telephony clusters.
Can manage IM and Presence upgrades and settings from the central cluster.
Lower cost option, particularly for large deployments with many Cisco Unified Communications Manager clusters
Easy XMPP Federation with third parties.
With a 25K OVA template, and a six-node cluster with High Availability enabled, the IM and Presence Service central deployment supports up to 75,000 clients. To support 75K users with 25K OVA, default trace level for XCP router needs to be changed from Info to Error.
Interclustering for Centralized Deployment
Interclustering is supported between two Centralize cluster. Intercluster is tested with one cluster with 25K ( with 25K OVA) and another with 15K (with 15K OVA) devices and no performance issues were observed.
Centralized Deployment Setup vs Standard Deployments
Differences with Standard Deployments
The installation process for an IM and Presence central deployment is the same as for the standard deployment. However, with central deployments, the IM and Presence central cluster is installed separatelyfrom your telephony cluster, and may be located on separate hardware servers. Depending on how you plan your topology, the IM and Presence central cluster may be installed on separate physical hardware from your telephony cluster.
For the IM and Presence central cluster, you must still install Cisco Unified Communications Manager and then install the IM and Presence Service on the same servers. However, the Cisco Unified Communications Manager instance of the IM and Presence central cluster is for database and user provisioning primarily, and does not handle voice or video calls.
Compared to standard deployments, the following extra configurations are required to set up the IM and Presence Service central deployment:
The following configurations, which are used withstandard deployments of the IM and Presence Service, are not required with Central Deployments:
|DNS SRV Configuration||
A DNS SRV that points to the publisher node of the connected telephony cluster is required. If you have an ILS network deployed, the SRV should point to the telephony hub cluster. For details, see DNS Requirements in the Prerequisites topic.
The SRV record is a Domain Name System (DNS) resource record that is used to identify computers that host specific services. SRV resource records are used to locate domain controllers for Active Directory.
The IM and Presence central cluster must have a DNS SRV record that points to the publisher node of the Cisco Unified Communications Manager telephony cluster. If your telephony deployment includes an ILS network, the DNS SRV must point to the hub cluster.
To verify DNS SRV locator resource records for a domain controller, use the following
Active Directory creates its DNS SRV records in the following folders, where Domain Name indicates the name of the installed domain.
Forward Lookup Zones/Domain_Name/_msdcs/dc/_tcp
In these locations, a DNS SRV record should appear for the following services:
_cisco_uds : Indicates the DNS SRV record
The below mentioned parameters has to be set during the DNS SRV record creation .
Protocol : _tcp
priority : starts form 0 (0 is the highest priority)
weight : starts from 0 (0 is the highest priority)
port no : 8443
host : fqdn name of the server
Centralized Cluster Deployment Architecture
The following diagram highlights the cluster architecture for this deployment option. Cisco Jabber clients connect to multiple Cisco Unified Communications Manager clusters for voice and video calling. In this example, the Cisco Unified Communications Manager telephony clusters are leaf clusters in a Session Management Edition deployment. For Rich Presence, Cisco Jabber clients connect to the IM and Presence Service central cluster. The IM and Presence central cluster manages instant messaging and presence for the Jabber clients.
Your IM and Presence cluster still contains an instance for Cisco Unified Communications Manager. However, this instance is for handling shared features such as database and user provisioning–it does not handle telephony.
Centralized Cluster Use Case
To connect your telephony and IM and Presence clusters, a new system for exchanging access keys is introduced. This diagram shows the flow for SSO logins:
-: Query DNS to get SRV record.
-: Query UDS to get the Home Cisco Unified Communications Manager cluster.
-: Get Access Token and Refresh Token from Cisco Unified Communications Manager cluster through SAML SSO.
: Read UC Service Profile. The service profile contains an IM and Presence profile and points to the IM and Presence central cluster.
: Client registers to the IM and Presence cluster using the same Access Token through SOAP and XMPP interfaces.
: The token is validated and a response is sent back to Jabber client.