Cisco CallManager User Database

Cisco CallManager stores most configuration information for the voice network in the underlying SQL 2000 database infrastructure. However, user information does not fall under this category; rather, the user information is stored in a separate database accessible through the Lightweight Directory Access Protocol (LDAP). LDAP is an industry standard protocol that allows applications to access and potentially modify information stored in the database. Cisco decided to keep the user database separate from the rest of the CallManager configuration because network administrators might want to harness their existing corporate directory (that is already filled with user information used to access the data network) for the voice network.

By default, Cisco CallManager uses an embedded LDAP directory that installs with the CallManager software image. This directory is called DC Directory. However, you can also choose to use your existing corporate directory as the CallManager user database. CallManager supports the following directory integrations as of version 3.3(3) and 4.0(1)sr2:

• Microsoft Active Directory 2000
• Microsoft Active Directory 2003
• Netscape Directory Server 4.x
• iPlanet/Sun Directory Server 4.1

Although integrating Cisco CallManager with the corporate directory provides tremendous advantages, there are equally tremendous caveats to this configuration:

• To integrate with a corporate directory, the network administrator must modify the schema of that directory. This is a networkwide change that affects all servers participating in the replication of the corporate directory and might cross political boundaries in the organization.
• The CallManager servers must be able to access the corporate directory servers at all times. Failure of this communication will result in authentication failures (and equipment inoperability) in the voice network.
• The additional read/write operations on the corporate directory will result in additional load for the servers maintaining this directory. An overlay of the voice network to your network infrastructure can potentially double the number of requests to the corporate directory servers.

Note

Because the process of integrating the Cisco CallManager into an LDAP corporate directory differs greatly depending on the type of directory service you are using and its configuration, we will assume you are using the embedded DC Directory service for the remainder of this text. The Cisco website and CallManager SRND documentation provides detailed instructions if you are considering this integration.

The following CCO link also provides excellent information about Active Directory integration:

http://www.cisco.com/en/US/products/sw/voicesw/ps556/products_implementation_design_guide_chapter09186a0080447505.html#wp1043120