ActiveCast: Toward Application-Friendly Active Network Services

The next step in the evolution of active networks — one that will support radical new uses of the network and increased scalability — is packaging the power of a programmable network platform into customizable active services that are easy for applications to use. The Activecast project has been developing and evaluating a set of active services that will not only enhance the “applicationfriendliness” of active networks, but will also improve the scalability and usability of networks in general. This paper discusses the challanges of programming active networks and then presents four new active network services, PAMcast, Concast, ESP, and LWP, that simplify the task of programming active networks. PAMcast services allow messages to be sent to any node(s) satisfying a set of user-supplied selection criteria. The Concast service provides the logical inverse of multicast, gathering and merging data from a set of senders. Finally, the ESP and LWP services provide extremely lightweight buildingblocks on which additional higher-level semantic services can be constructed. For each service, we describe the service abstraction, the ways in which users can customize the service, and its ease of use (i.e., how the customized service is automatically distributed across and “programmed” into the network on the user’s behalf). We also present results from simulation models and actual implementations of the new services that demonstrate the scalability and performance of the services. This work sponsored in part by the Defense Advanced Research Projects Agency (DARPA) and the Air Force Research Laboratory, Air Force Materiel Command, USAF, under agreement number F30602-99-10514; and by the National Science Foundation under grant numbers EPS9874764 and EIA-0101242. Views and conclusions contained herein are those of the authors and should not be interpreted as representing the official policies or endorsements, either expressed or implied, of the Defense Advanced Research Projects Agency, the Air Force Research Laboratory, or the U.S. Government. The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright annotation thereon.