Long Usernames

Enterprise Server has provisions for supporting usernames that do not meet the mainframe convention of 1-8 characters from a restricted character set. These mainframe-style usernames are conventionally referred to as "short names". Usernames that are not mainframe-compatible are called "long names", even though they are not necessarily longer than eight characters. For example, since spaces are not allowed in short usernames, a six-character username containing a space would be considered a "long" name.

Since Enterprise Server's Mainframe Subsystem Support (MSS) features must remain mainframe-compatible when dealing with usernames, MSS and other Enterprise Server components use short names internally.

In effect, "long name" means "the username outside Enterprise Server", while "short name" means "the alias used in Enterprise Server". If you are not using the long-name feature, those two are the same.

If you make use of the long-name feature:

• In most cases, when users enter their username, they use the long name. This includes user interfaces such as the MFDS Enterprise Server Administration tool and command-line utilities such as casstart. The main exceptions are the CICS signon transactions CESN and CESL; the underlying CICS APIs such as EXEC CICS SIGNON; and the USER parameter of JCL job cards. For mainframe compatibility those are still restricted to eight characters and so must use the short name.
• If an application running in MSS queries the user's name, the short name is returned.
• Under the External Security Facility (ESF):
  • External Security Manager (ESM) Modules verify the user by long name. For the MLDAP ESM Module, user-group membership is specified using the long name.
  • ESF resource access checks use the short name.

  That is, when establishing a user's identity, the long name is used. That includes discovering all the attributes of a user, such as group membership. When operating on a user's identity, the short name is used.