An Authentication ID is an identifier that is used by a client to identify itself to the Directory Server for certain kinds of SASL Mechanisms (e.g., CRAM-MD5 SASL Mechanism, DIGEST-MD5, and PLAIN SASL Mechanism). It can be used to allow a client to identify itself with a username (or other friendly identifier) rather than a DN.
In most cases, an Authentication ID should be specified in one of the following forms: