Computer Networks:

1.Consider a message of 4 data bits is tranemitted from the source to its destination. The 4-bit message string to be coded is given as 1101.Please answer the following question.

a.Assume that the even parity check is applied for error detection. What is the codeword of the message generated by the even parity check?

b.Assume that the cyclic redundancy code (CRC) is applied for error detection.Let g(x)=x^3+x+1.

1.Find the codeword for the given message string.

2.suppos that the code word has a transmission error in the first bit. What does the destination obtain when it does its error checking?

2. Consider 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 transmitthat isthe polling delayis D seconds. Suppose that within a polling round given node is allowed to transmit at most Q bits. What is the maximum throughput of the broadcast channel?10