Answer Happy

a) Suppose the information content of a packet is the bit pattern 1110 0110 1001 1101 and an even parity scheme is being used. What would the value of the field containing the parity bits be for the case of a two- dimensional parity scheme? Demonstrate using your answer that two- dimensional parity checks can correct and detect a single bit error. b) Suppose four active nodesnodes A, B, C and D-are competing for access to a channel using slotted ALOHA. Assume each node has an infinite number of packets to send. Each node attempts to transmit in each slot with probability p. What is the probability that node A succeeds for the first time in the second slot? a c) Consider a broadcast channel with N nodes and a transmission rate of R bps. Suppose the broadcast channel uses polling (with an additional polling node) for multiple access. Suppose the amount of time from when a node completes transmission until the subsequent node is permitted to transmit (that is, the polling delay) is dpoll. Suppose that within a polling round, a given node can transmit at most Q bits. What is the maximum throughput of the broadcast channel, i.e. how many bits per second are being transmitted in the network?