RFC 2970 (rfc2970) - Page 2 of 18
Architecture for Integrated Directory Services - Result from TISDAG
Alternative Format: Original Text Document
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