Laharsub: HTTP REST pub/sub service for AJAX and Silverlight web clients

I would like to invite you to review, download, use, tweak, and provide feedback for an experimental project we launched at Codeplex: Laharsub (

Laharsub project on Codeplex

We have been getting comments and observing the dominant use case scenarios for the HTTP Polling Duplex protocol for a few releases of Silverlight now. It is clear there are areas of improvement for how polling duplex works, but it is also apparent we can add value by addressing key higher level scenarios and application patterns. At this point we would like to ask you to help us decide where we should be investing going forward by providing feedback about the project.

This is the high level abstract of the project:

Laharsub ( is a new open source project that provides web applications with the ability to exchange messages at the internet scale using the publish\subscribe pattern. The HTTP REST protocol is optimized for web browser environment. It offers low latency of notifications with HTTP long polling, as well as connection usage optimization with subscription multiplexing. Currently the project ships with a jQuery extension for easy integration with jQuery clients, and a server implementation based on Windows Communication Foundation (WCF) HTTP service in .NET Framework 4.0. The service can be extended with a variety of back end implementations depending on the requirements of the particular application.

If you have no time to look at, use, and run the actual [open source] code, perhaps you can review the way we look at the requirements at and the key design points.

Your feedback will be greatly appreciated!

Tomasz Janczuk
WCF Team