Many individuals throughout professional organisations will consider their list of personal and professional contacts as one of their most important assets. Similarly at home keeping our contact details of friends, relatives and professional service providers like physicians is also equally important, however maintaining that contact list across several computers can be very time consuming; even frustrating if it is lost.
Using the Lightweight Directory Access Protocol (LDAP) we can configure a centrally managed address book that can be shared by all the of computer workstations throughout the network (for many large organisations this is a fundamental design concept). A central (or shared) address book allows easy management of all contact details, it can be backed up and restored very easily, and it can also be made available through a secure web interface so it can be accessed remotely from where ever the user may be.
This chapter will detail the procedures necessary to configure the OpenLDAP (www.openldap.org) directory service that will provide the basis for our address book and make it available to our network users. We will also look at populating the address book and provide security access controls so that only authenticated users can access the information.

• Shared Address Book (LDAP)