A flow control scheme considering retransmissions in packet switched datagram transport networks

A flow control scheme based on differential access to memory resources in the network switches, depending on whether packets are offered from outside the network or have already been processed in the entry switch, was investigated. The protocol related to the transport network ensures that a packet accepted in the subnetwork is made available at the exit switch, retransmitting from the entry switch packets initially accepted and subsequently dropped due to shortage of buffer space in the exit switch until successfully forwarded to destination. The results show that retransmissions negatively impact on network preformance unless packets advanced beyond the entry switch are given exclusive, dynamic access to a portion of the buffer memory. The protocol guaranteeing delivery of accepted packets and featuring retransmission while favoring internal against external and retransmitted packets, performs similarly to the protocol in which packets dropped inside the transport network are resubmitted for delivery without exception from outside that subnetwork.