Access to Enterprise Server administrative features, MSS applications, and application resources are controlled by security managers. Sometimes referred to as an External Security Manager (ESM). Through the use of security managers, you can implement controls to verify users and their actions against permissions established in the operating system or in an LDAP repository.
You can configure multiple security managers in an installation's security manager pool. From the pool, you can create a default list of the security managers to use and lists for individual Enterprise Server. See About Security Managers and About Securing an Enterprise Server Installation for more information.