Flow Control in Reliable Multicast Protocol

A Flow Control in Reliable Multicast transport protocol over combined (Fixed/Mobile) networks called (FCRM) is proposed. FCRM is based on a hierarchical structure where receivers are grouped into local regions. In each local region, there are special receivers, which are called Designated Receivers (DRs) and Mobile Agents (MAs). Each DR or MA is responsible for retransmission of requested packets to the receivers which belong to its local region. DRs and MAs send their acknowledgments periodically to the sender. They also process the acknowledgments sent to them from the Fixed Hosts (FHs) and Mobile Hosts (MHs) and they retransmit lost packets to the requesting receivers. In this paper each DR or MA sends its empty buffer size with the acknowledgment packet. Thus, when the sender calculates its available window, it compares the empty buffer sizes of all DRs and MAs and takes the smallest among them and compares this value with the value of the calculated available window and the available window is taken as the smaller of them. Simulations (using C++) have demonstrated the scalability of FCRM.