SemCast: Semantic multiCast
Content-based Data Dissemination using Multicast

SemCast addresses the problem of content-based dissemination of highly distributed data streams for stream-based applications. SemCast provides a selective distributed information dissemination service, where routing is performed based on the content of the messages (content-based routing) rather than the IP addresses of the destinations. This dissemination service follows the publish/subscribe paradigm, decoupling data sources from the subscribed clients. The goal of SemCast is to efficiently identify and route relevant data to each client. The key idea is to split the data streams based on their content, the overlap of the clients subscriptions, the stream rates and the clients location, and spread the pieces across multiple semantic multicast channels. This approach can lead to significant improvement in the consumption of processing resources and bandwidth.

The key features of our approach are the following :

  1. Bullet    Efficient content-based filtering: SemCast requires filtering only at the sources and the final destinations, eliminating the need for hop-by-hop content-based filtering performed in traditional content-based publish/subscribe systems.

  1. Bullet    Flexibility:  SemCast disseminates each sub-stream through an independent dissemination channel and thus, it facilates fine-control over the construction of the multicast trees.

  1. Bullet    Adaptivity:  SemCast  continuously monitors  the system's characteristics and adapts to changes in the overlap among the subscriptions, the rate of the incoming streams and the location of the clients by reevaluating its channelization decisions.

  This project is superseded by the XPORT project.


  1. Bullet    O. Papaemmanouil and U. Cetintemel, SemCast: Semantic Multicast for Content-based Data Dissemination. In proceedings of the 21st International Conference on Data Engineering (ICDE'05), April 2005, Tokyo, Japan. [pdf]

  1. Bullet    O. Papaemmanouil and U. Cetintemel, Semantic Multicast for Content-Based Stream Dissemination. In proceedings of the 7th International Workshop on the Web and Databases (WebDB04), June 2004, Paris. [pdf]


  1. Bullet    Ugur Cetintemel

  2. Bullet    Olga Papaemmanouil

  3. Bullet    Austin Park