RFC 2970 (rfc2970) - Page 2 of 18

Architecture for Integrated Directory Services - Result from TISDAG

RFC 2970       Architecture for IDS - Result from TISDAG    October 2000


   The proposed architecture inserts a coordinated set of modules
   between the client access software and participating servers.  While
   the client software interacts with the service at a single entry
   point, the remaining modules are called upon (behind the scenes) to
   provide the necessary application support.  This may come in the form
   of modules that provide query proxying, schema translation, lookups,
   referrals, security infrastructure, etc.

   Part of this architecture is an "internal protocol" -- called the
   "DAG/IP" in the TISDAG project.  This document also outlines the
   perceived requirements for this protocol in the extended DAG.

2.0 Some terminology

   Terms used in this document are compliant with those set out in
   [ALVE]. For the purposes of this document, important distinctions and
   relationships are defined between applications, services, servers and
   systems.  These are defined as follows:

   Application:  this is meant in the general sense, as a solution to a
     particular (set of) user need(s).  That is, the definition is not
     tied to a particular piece of software (as in "application
     program").

     The definition of an application includes the type(s) of
     information to be exchanged, expected behavior, etc.  Thus, a
     whitepages (search) application may expect to receive a name as
     input to a query engine, and will return all information associated
     with the name.  By contrast, a specific security application might
     use the same input name to verify access controls.

   Service:  an operational system providing (controlled) access to
     fulfill a particular application's needs.

     One service may be changed by configuring location, access
     controls, etc.  Changing application means changing the service.

   Server:  a single component offering access through a dedicated
     protocol, without regard to a specific service (or services) it may
     be supporting in a given configuration. Typically programmed for a
     particular application.

   System:  a set of components with established interconnections.

     Thus, a service can be split between several servers.  A collection
     of services (independently, or interrelated through specified
     agreements) act as an implementation of an application.  A system
     is composed of one or more servers and services.



Daigle & Eklof               Informational