2.7.14 Reliable Server Pooling (rserpool)

NOTE: This charter is a snapshot of the 49th IETF Meeting in San Diego, California. It may now be out-of-date. Last Modified: 04-Dec-00


Lyndon Ong <long@pointreyesnet.com>
Maureen Stillman <maureen@oracorp.com>

Transport Area Director(s):

Scott Bradner <sob@harvard.edu>
Allison Mankin <mankin@east.isi.edu>

Transport Area Advisor:

Scott Bradner <sob@harvard.edu>

Technical Advisor(s):

Ned Freed <ned.freed@innosoft.com>

Mailing Lists:

General Discussion:rserpool@standards.nortelnetworks.com
To Subscribe: listserv@standards.nortelnetworks.com
Archive: http://standards.nortelnetworks.com/archives/rserpool.html

Description of Working Group:

The purpose of the WG is to develop an architecture and protocols for the management and operation of server pools supporting highly reliable applications, and for client access mechanisms to a server pool.

The WG will define architecture and requirements for management and access to server pools, including requirements from a variety of applications, building blocks and interfaces, different styles of pooling, security requirements and performance requirements, such as failover times and coping with heterogeneous latencies. This will be documented in an Informational RFC.


The working group will focus on supporting high availability and scalability of applications through the use of pools of servers. This requires both a way to keep track of what servers are in the pool and are able to receive requests and a way for the client to bind to a desired server.

The Working Group will NOT address:

1) reliable multicast protocols - the use of multicast for reliable server pooling is optional. Reliable multicast protocols will be developed by the RMT WG.

2) synchronization/consistency of data between server pool elements, e.g. shared memory

3) mechanisms for sharing state information between server pool elements

4) Transaction failover. If a server fails during processing of a transaction this transaction may be lost. Some services may provide a way to handle the failure, but this is not guaranteed.

The WG will address client access mechanisms for server pools, specifically:

1) An access mechanism that allows geographically dispersed servers in the pool

2) A client-server binding mechanism that allows dynamic assignment of client to servers based on load balancing or application specific assignment policies.

3) Support of automatic reconfiguration of the client/server binding in case of server failure or administrative changes.

To the extent that new protocols are necessary to support the requirements for server pooling, these will be documented in a Standards Track RFC on client access to a binding service (i.e. name space) protocol.

The WG will also address use of proxying to interwork existing client access mechanisms to any new binding service.

The WG will address server pool management and a distributed service to support client/server binding, including:

1) A scalable mechanism for tracking server pool membership (incl. registration)

2) A scalable protocol for performing node failure detection, reconfiguration and failover, and otherwise managing the server pool (supporting caching, membership, query, authentication, and security)

3) A distributed service to support binding of clients to servers, based on information specific to the server pool. Given that this service is essential to access the server pool, a high degree of availability is necessary.

4) A means for allowing flexible load assignment and balancing policies

The protocols and procedures for server pool management will be documented in a Standards Track RFC.

The WG will address:

- transport protocol(s) that would be supported (eg. UDP, SCTP, TCP)

- any new congestion management issues

- relationship to existing work such as URI resolution mechanisms

Rserpool will consult with other IETF working groups such as Reliable multicast, DNS extensions, AAA, URN, WREC and Sigtran as appropriate and will not duplicate any of these efforts.

Goals and Milestones:

Dec 00


Initial draft of RSPool Requirements And Architecture document

Jan 01


Submit Reqts and Architecture draft to IESG for consideration as an Informational RFC

Mar 01


Initial draft of Binding Service document

Jun 01


Initial draft of Client/server binding and Server Pool Management document

Sep 01


Submit drafts of Binding Service and Server Pool Management to IESG for consideration as Proposed Standard RFCs

No Current Internet-Drafts
No Request For Comments

Current Meeting Report

Reliable Server Pools Working Group (rserpool)

Friday, December 15 at 0900-1130

CHAIRS: Lyndon Ong (long@pointreyesnetworks.com)
Maureen Stillman (maureen.stillman@nokia.com)

This was the first official meeting of the reliable server pooling working group. We began with a discussion of requirements for reliable server pooling. Michael Tuexen gave a presentation based on an internet draft. This was summary of activity on the mailing list over the past several months. A lively debate of requirements ensued and new requirements uncovered. The group voted to make this requirements document draft-tuexen-rserpool-reqts-01.txt a working group document. It will continue to be refined and debated on the mailing list.

A variety of relevant scenarios were presented and extensively debated to motivate an architecture definition. These scenarios included:

- FTP: Randy Stewart
- E-commerce: Michael Tuexen
- Telephony: Lyndon Ong
- IP Radio Access Networks (RAN): John Loughney

The consensus of the group was to continue work on the architecture over the mailing list.


None received.