Subject: WG Review:LDAP Duplication/Replication/Update Protocols (ldup)

From: Steve Coya <[email-masked]>
Date: Mon, 26 Oct 1998 08:11:20 -0500

A new IETF working group has been proposed in the Applications Area.
The IESG has not made any determination as yet. 

The following Description was submitted, and is provided for
informational purposes only:

Description of Working Group:

As LDAPv3 becomes more widely deployed, replication of data across
servers running different implementations becomes an important
part of providing a distributed directory service. However, the LDAPv3
community, to date, has focused on standardizing the client-server
access protocol. Therefore, this group will standardize master-slave
and multi-master LDAPv3 replication as defined below:

o Multi-Master Replication -  A replication model where entries can be 
  written and updated on any of several replica copies, without
  requiring communication with other masters  before the write or
  update is performed.

o Master-Slave, or Single-Master Replication - A replication model that 
  assumes only one server, the master, allows write access to the 
  replicated data. Note that Master-Slave replication can be considered 
  a proper subset of multi-master replication.

The WG's approach is to first develop a set of requirements for LDAPv3
directory replication and write an applicability statement defining
scenarios on which replication requirements are based. An engineering
team was formed consisting of different vendors and the co-chairs in
order to harmonize the existing approaches into a single standard
approach. All of these have been accomplished during the pre-working
group stage. It should be noted, however, that replication using
heterogeneous servers is dependent on resolving access control issues,
which are the domain of other working groups.

The new replication architecture support all forms of replication
mentioned above. Six areas of working group focus have been identified
through LDUP Engineering Team discussions, each leading to one or
more documents to be published:

o Abstract Model of LDAPv3 Replication

  This documents a general-purpose LDAPv3 replication architecture, 
  defines key components of this architecture, describes how these key 
  components functionally behave, and describes how these components 
  interact with each other when in various modes of operation

o LDAPv3 Replication Information Model

  Defines the schema and semantics of information used to operate, 
  administer, maintain, and provision replication between LDAPv3 
  servers. Specifically, this document will contain common schema 
  specifications intended to facilitate interoperable implementations 
  with respect to:

  + replication agreements
  + consistency models
  + replication topologies
  + managing deleted objects and their states
  + administration and management

o LDAPv3 Replication Information Transport Protocol

  LDAPv3 extended operation and control specifications required to allow 
  LDAPv3 to be used as the transport protocol for information being 
  replicated

o LDAPv3 Mandatory Replica Management

  Specifications required to allow administration, maintenance, and 
  provisioning of replicas and replication agreements. These 
  specifications may take the form of definitions for LDAPv3 extended
  operations, controls, and/or new schema elements.

o LDAPv3 Conflict Detection and Resolution Procedures

  Procedures for detection and resolution of conflicts between the state 
  of multiple replicas that contain information from the same unit of 
  replication.

o LDAPv3 Profiles

  Including the Abstract Replication Model, Information Model, LDAPv3 
  Protocol Extensions, and Conflict Detection and Resolution Procedures 
  for:

  + Master-Slave LDAPv3 Directory Replication
  + Multi-Master LDAPv3 Directory Replication