Scheduling of multicast traffic in high-capacity packet switches

As the traffic on the Internet grows, better quality of service should be provided to users. We have proposed earlier the weighted sequential greedy scheduling (WSGS) protocol that provides fast bandwidth reservations in terabit packet switches with input buffers. In switches with input buffers, a port that sources a multicast session might easily get congested as it becomes more popular. In this paper, we extend WSGS to support varying popularity of content on the Internet. Destination ports forward copies of multicast packets to other destination ports in a specified order. In this way, the multicast traffic load is evenly distributed over switch ports. The performance trade-off between capacity that can be reserved and guaranteed packet delay are discussed.