A Queueing Model for Optimal Segmentation of a Token-Ring Local Area Network

In a token-ring LAN the nodes (labeled i = l,. .., n) are arranged logically in a ring with each node transmitting to the next node in the ring. There is a single token and a node must be in possession of it in order to transmit a packet. Each intermediate node receives the packet and retransmits it, with a time delay'd'. When the node completes transmitting the packet it appends the token to the end of the packet, thus indicating to the next (downstream) node that it may begin transmitting. If it does not have a packet to transmit, it passes on the token.