RFC 3402 DDDS - The Algorithm October 2002 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 3. The Algorithm . . . . . . . . . . . . . . . . . . . . . . . . 4 3.1 Components of a Rule . . . . . . . . . . . . . . . . . . . . . 6 3.2 Substitution Expression Syntax . . . . . . . . . . . . . . . . 6 3.3 The Complete Algorithm . . . . . . . . . . . . . . . . . . . . 8 4. Specifying An Application . . . . . . . . . . . . . . . . . . 9 5. Specifying A Database . . . . . . . . . . . . . . . . . . . . 11 6. Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 6.1 An Automobile Parts Identification System . . . . . . . . . . 12 6.2 A Document Identification Service . . . . . . . . . . . . . . 14 7. Security Considerations . . . . . . . . . . . . . . . . . . . 15 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 15 References . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Author's Address . . . . . . . . . . . . . . . . . . . . . . . 16 Full Copyright Statement . . . . . . . . . . . . . . . . . . . 17 1. Introduction The Dynamic Delegation Discovery System (DDDS) is used to implement lazy binding of strings to data, in order to support dynamically configured delegation systems. The DDDS functions by mapping some unique string to data stored within a DDDS Database by iteratively applying string transformation rules until a terminal condition is reached. This document describes the general DDDS algorithm, not any particular application or usage scenario. The entire series of documents is specified in "Dynamic Delegation Discovery System (DDDS) Part One: The Comprehensive DDDS" (RFC 3401) [1]. It is very important to note that it is impossible to read and understand a single document in that series without reading the related documents. The DDDS's history is an evolution from work done by the Uniform Resource Name Working Group. When Uniform Resource Names (URNs) [6] were originally formulated there was the desire to locate an authoritative server for a URN that (by design) contained no information about network locations. A system was formulated that could use a database of rules that could be applied to a URN to find out information about specific chunks of syntax. This system was originally called the Resolver Discovery Service (RDS) [7] and only applied to URNs. Mealling Standards Track