The past two decades have seen a great deal of effort invested
in developing multicast technology for the Internet.
Unfortunately, early excitement about multicast has
given way to frustration with the challenges of
designing and deploying a scalable multicast service.
The reaction to this situation
has been an explosion in different implementation
techniques designed for specific applications.
None of these new services have been widely deployed.
Multicast technology today is complex and
confusing to application writers.
We propose a multicast session layer
to address this complexity.
This new layer will simplify the
development of multicast applications and ease the
deployment of new multicast technology by
decoupling the service model and programming interface
from the underlying implementation.
The case for a multicast session layer is presented
and a possible implementation is outlined.
