Token Bus was a proprietary Ethernet-based network. It worked like Token Ring in that a small token packet was sent from one station to the next in agreed-upon order, and a station could transmit only when it had just received the token.

(a). If the data rate is 10 Mbps and the token is 64 bytes long (the 10-Mbps Ethernet minimum packet size), what is the average wait to receive the token on an idle network with 40 stations? (The average number of stations the token must pass through is 40/2 = 20.) Ignore the propagation delay and the gap Ethernet requires between packets.

(b). Sketch a protocol by which stations can sort themselves out to decide the order of token transmission; that is, an order of the stations S0 ... Sn-1 where station Si sends the token to station S(i+1) mod n.