I don't know about Macs specifically (Apple makes servers?) or why they aren't using Kerb, but LDAP is commonly used over SSL/TLS. "LDAPS" some call it. LDAP w

I don't know about Macs specifically (Apple makes servers?) or why they aren't using Kerb, but LDAP is commonly used over SSL/TLS. "LDAPS" some call it. LDAP wasn't originally designed to be an authentication protocol. If Mac clients are using it to make authentication decisions, they had better be requiring SSL/TLS on that connection (and validating the server cert perfectly, too).