In this chapter, we looked at a variety of network-based authentication systems, including Sun's Network Information Service (NIS), Sun's NIS+, Kerberos, and LDAP. We also looked at how the Pluggable Authentication Module (PAM) system can be used to transparently integrate any of these authentication systems with a wide variety of modern Unix offerings.
There are many network-based authentication systems. If you have more than a few computers to administer, it is likely that you will chose to deploy one or more of these systems. No matter what you use, be sure that all authentication information sent across your network is encrypted. And be sure that the system you plan to deploy runs on all of the computers that you wish to support. Otherwise, your system may cause more problems than it solves.