Curious hospital staff peeking at medical records of famous people. Snoopers grabbing passwords and tunneling through a private network. Practical jokers changing documents under their authors' noses. Network security affects all of us. Here lies one of the greatest strengths of the Distributed Computing Environment (DCE) from the Open Software Foundation (OSF). DCE offers the most complete, flexible, and well-integrated network security package in the industry. The heart of DCE Security lies in access control lists (ACLs). But before you start to play with these, you have to do some design work. For instance, ACLs need to be stored on disk so that they can last between runs of the application. This book helps you plan your application and lay the groundwork for ACLs, as well as use the calls that come with the DCE Security interfaces. It covers the purpose of DCE Security, how the whole system fits together, what is required of the programmer, and how to figure out what needs protection. Using a sample application, increasingly sophisticated types of security are discussed: authenticating and authorizing the client and server; using ACLs for authorization; and the notorious, dreaded ACL manager. This book focuses on version 1.0 of DCE. However, issues in version 1.1 are also discussed so that you can migrate to that interface.