The DIGEST-MD5 mechanism authenticates clients by comparing a hashed value sent by the client with a hash of the user's password. However, because the mechanism must read user passwords, all users wishing to be authenticated through DIGEST-MD5 must have clear text passwords in the directory.
GSSAPI is available on the Solaris Operating System only. The General Security Services API (GSSAPI) allows Directory Server to interact with the Kerberos V5 security system to identify a user. The client application must present its credentials to the Kerberos system, which in turn validates the user's identity to Directory Server.
For information about how to configure SASL-based authentication, see Configuring Client Authentication in Sun Java System Directory Server Enterprise Edition 6.0 Administration Guide.