DDDS
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The Dynamic Delegation Discovery System (DDDS) is used to implement
lazy binding of strings to data, in order to support dynamically
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... 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
...
... 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
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... 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 ...
... 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 ...
... Dynamic Delegation Discovery System (DDDS)
Part One: The Comprehensive DDDS" (RFC 3401) [1]. It is very
...
... 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 ...
... infrastructure to other, non-URN related, systems (see Section 6 for
examples of other ways of using the DDDS). This caused some of the
underlying assumptions to change and need clarification. These
documents are an update ...
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Application Unique String
A string that is the initial input to a DDDS application. The
lexical structure of this string must imply a unique delegation
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... Terminal Rule
A Rewrite Rule that, when used, yields a string that is the final
result of the DDDS process, rather than another database key.
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... A set of protocols and specifications that specify actual values
for the various generalized parts of the DDDS algorithm. An
Application must define the syntax and semantics of the
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...
The DDDS algorithm is based on the concept of Rewrite Rules. These
rules are collected into a DDDS Rule Database ...
... The DDDS algorithm is based on the concept of Rewrite Rules. These
rules are collected into a DDDS Rule Database, and accessed by given
unique keys. A given Rule, when applied to an Application Unique
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... It is a fundamental assumption that the Application Unique String has
some kind of regular, lexical structure that the rules can be applied
to. It is an assumption of the DDDS that the lexical element used to
make a delegation ...
... make a delegation decision is simple enough to be contained within
the Application Unique String itself. The DDDS does not solve the
case where a delegation decision is made using knowledge contained
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... | +----<--------------<--------------+
| | |
| key (a DDDS database always |
| +-----+ takes a key and returns |
| |input| a rule) ^
...
... | +---------+ +------------+ |
| | Lookup key in DDDS Database| |
| +---------+ +-----------+ |
| |output| |
...
... Database
being used. An Application must define what the allowed character
sets are for the Application Unique String. A DDDS Database
specification must define what character sets are required for
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...
The following is the exact DDDS algorithm:
1. The First Well Known Rule is applied to the Application Unique
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... state where the rules for that application are
suspended and a new DDDS Application or some other arbitrary set
of rules take over. If this is the case then, by definition, none
of these rules apply. One such case can be found in the URI
Resolution ...
... URI
Resolution application which defines the 'p' flag which states
that the next step is 'protocol specific' and thus outside of the
scope of DDDS.
First Well Known Rule:
...
... In the past there has been some confusion concerning load balancing
and the use of the DDDS 'Priority'. Applications should be aware
that the Priority ...
... client to load balance
between servers (i.e., weighted random selection, etc.) then it
should do so outside the DDDS algorithm. For example, Applications
that make use of the DNS Database ...
... load
balancing is done between hosts that are identical to each other
where as DDDS is concerned with delegation paths that have some
particular feature set ...
... a query is formulated specifically for the database to be a DDDS
database. For example, a DNS based Database must specify which
...
... manufacturer decides.
The auto industry decides to use the DDDS to create a distributed
information retrieval system that routes queries ...
... for retrieving rewrite rules (the APIDA Network) and then specifies
the Auto Parts Identification DDDS Application (APIDA).
The APIDA specification would define the following:
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This document simply defines the DDDS algorithm and thus, by itself,
does not imply any security issues. It is when this algorithm ...
... Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part One: The Comprehensive DDDS", RFC 3401, October 2002. ...
... Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part One: The Comprehensive DDDS", RFC 3401, October 2002. ...
... Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part Three: The Domain Name System (DNS) Database ...
... Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part Four: The Uniform Resource Identifiers (URI) Resolution Application", RFC 3404prop ...
... Mealling, M., "Dynamic Delegation Discovery System (DDDS) Part Five: URI.ARPA Assignment Procedures", RFC 3405 ...