Multicast packet control apparatus

Abstract

When multicast distribution is performed on a network where a point-to-point connection is made between user terminals and a multicast router, the multicast router is protected from load due to response reports, join requests, or leave statements sent from the user terminals simultaneously. If the user terminals send response reports simultaneously, a Layer 2 switch disposed between the user terminals and the multicast router limits response reports sent to the multicast router. The Layer 2 switch prevents response reports sent from the same user terminal from being discarded consecutively, by sending a response report sent from the same user terminal to the multicast routerwith priority in the next join confirmation event. If the user terminals send join requests or leave statements simultaneously, the Layer 2 switch limits the join requests or leave statements sent to the multicast routerin the same manner. The Layer 2 switch further enlarges a transmission buffer thereof at the multicast router side, so that the packets can be stored in the buffer.