Re: Directory Service

Some personal observations ...

The database:

• Heirarchical database, not relational. Schema is moderately flexible.
• Frequently implemented in flat files. (Can you say "what is scalability? what is reliability?")
• Oracle has implemented the heirarchy in relational tables. (Do not attempt to understand the dictionary unless you are adequately 'wasted'. We're talking a 'dynamic pivot table' kind of phenomena!)
• Traditional tools (SQL*Plus, etc.) not recommended (unless you enjoy having a .44 pointed at your foot). Use the supplied admin tools!
• The Oracle9iDB is used for the data store.

Accessing LDAP:

• Implemented by processes listening on a specific port.
• Traditionally 1 process/machine, 1 machine/'directory'
• multiple machines = multiple databases which are kept in sync using ???? (more processes!)
• Traditional process (frequently single threaded) is responsible for catching request as well as data management.
• User's request intercepted by process, process looks up info & (usually) returns same "record" with blanks filled in or 'Found=Yes/No' response.
• Oracle's implementation allows multiple, lighter processes per machine, all talking to one database. This supports distributed architecture, etc.
• At least part of the LDAP processes in Oracle are/were only available through the 9iAS; possibly just those interfaces between Oracle's LDAP and other directories. (Check OTN!)

In an Oracle environment: (there may be licening implications)

• called Oracle Internet Directory (had that name for 3 years - time for a name change?)
  • it can be used to replace Names Servers
• it can be used to provide a single "central security repository" to keep all userid/authentication/authorization info.
• it can be extended to add new types of info
• it can interface with other directories (Novell, Active Directory, etc.)
• it can interface to an HR system to automatically keep the info up to date