Avis is a high-performance event router. It provides a fast publish/subscribe event routing service compatible with the commercial Elvin implementation developed by Mantara Software.
Fast broadcast message delivery. No requirement to support transactions or persistence, plus concise message selection allows near real-time delivery.
Flexible message format. Messages are just name-value pairs.
Content-based subscription. Select messages using subscription expressions like
From == 'logger' && Severity > 3or
(string (Message) && Timeout > 0) || regex (Message, 'News:.*').
Federation of multiple message routers. Replicate selected messages between any configuration of routers to form local and wide-area message networks.
Security. Supports per-subscription access control and SSL/TLS client/server authentication and encryption.
Simplicity. No external dependencies and no configuration required. Avis runs on any platform that supports Java 5 or later.
Client libraries for Java and C. Write Avis clients for a wide variety of platforms.
Current uses for Elvin routers include providing a message bus for instant messaging and presence, device discovery and coordination for Livespace smart meeting rooms, and as a carrier of distributed speech transcription for meetings. The commercial implementation developed by Mantara has been used extensively for high-volume real-time financial transaction routing.
Avis is a compatible drop-in replacement for Mantara's commercial
elvind if quenching (for discovery of subscriptions) is not
required. Avis also supports federation with other
See the roadmap page for more information on what's planned for Avis.
Elvin orginated as a project at the Distributed Systems Technology Centre (DSTC), a Cooperative Research Centre, which operated from 1992 until mid 2006. During this time Elvin was incorporated into a number of DSTC projects and adopted by several of DSTC's partners, such as the Australian Defence Science and Technology Organisation (DSTO).
In 2003 Mantara Software Inc was created as a DSTC spin-off commercial entity in order to further develop and market Elvin. When Mantara announced it would stop offering Elvin as a stand-alone product, Matthew Phillips implemented the Elvin open specifications published at elvin.org as free software in the form of the Avis project.
The Avis project aims to support ongoing development using the proven Elvin message bus approach. It is intended that Avis will track developments in the Elvin specifications in order to remain a compatible long-term option.
The name "Avis" derives from the French word avis, meaning advice or notification.
The lead developer of the Avis project, Matthew Phillips,
can be contacted at
avis at mattp.name or
users.sourceforge.net (replace "at" with "@").