1. Consider the TCP basic congestion control algorithm employing slow start and congestion avoidance. Let the packet dropping probability p be constant and independent of the window size. a. Given that the window size when a packet drop takes place is W, find the mean time until another packet drop takes place. b. Given that the number of bytes per packet is B, find the mean number of bytes transmitted during the above interval. 2. In this problem, we would like to consider the effect of using different window reduction strategies, upon congestion detection, on the recovery from congestion. Using one TCP session, assume that a router becomes saturated, i.e., input rate = output rate, when the window size is W, and the round trip time is R. If the buffer capacity in the router is B, the buffer is empty when saturation occurs, and the TCP source is in the linear window increase phase, i.e., it is increased by one segment every one round trip time, answer the following: a. Find the number of round trip times that are required for a packet to be dropped in the router, and the TCP window size at that moment. b. Assuming that every time a window encounters a packet drop, the window size is reduced linearly, i.e., reduced by A packets, find the time until the router becomes unsaturated again, and the number of packets lost during that interval (assume that one or more packets being dropped from a window will result in just one reduction). c. Repeat the above part but using a geometric window reduction strategy, i.e., the window is reduced by B.W, where &beta is a constant, and W is the window size when a loss occurs. d. Based on the above, indicate which strategy should be used (you may use numerical examples to help you arrive at a conclusion). 3. Using a list, or a table, compare the SCTP and MPTCP protocols, explaining what each of the two protocols can implement, and whether the other protocol is able to implement or not Then, draw a conclusion as to which of the two protocols is more superior. 4. Under IPv6, fragmentation is implemented in end nodes only, unlike IPv4 where fragmentation can be done inside the network. This reduces the amount of processing inside the network. However, it may increase the amount of bandwidth consumption. If the packet header is H, and a packet has to go over N networks, 1, 2, ..., N, where the maximum transmission unit of network i, MTU, is such that MTU = 2. MTU+1 for i=1, 2, ..., N-1. Find the total number of overhead bits under both IPv4 and IPv6 if the initial packet size is equal to MTU.