Authentication mechanisms
Saslauthd supports one or more authentication mechanisms, dependent upon the facilities provided by the underlying operating system. The mechanism is selected from the following list of choices:

dce(AIX)
getpwent(All platforms)
kerberos4(All platforms)
kerberos5 (All platforms)
pam(Linux, Solaris)
rimap(All platforms)
shadow(AIX, Irix, Linux, Solaris)
sasldb(All platforms)
ldap(All platforms that support OpenLDAP 2.0 or higher)
sia(Digital UNIX)