CS 118 Spring 2008 : ProblemsProblem 1Problem 1Suppose nodes A and B are on the same 10Mbps Ethernet bus, and the propagation delay between thetwo nodes is 255 bit times.Suppose node A begins transmitting a frame and, before it finishes, node Bbegins transmitting a frame.Can A finish transmitting before it detects that B has transmitted?Whyor why not?If the answer is yes, then A incorrectly believes that its frame was successfully transmittedwithout a collision.Hint:Suppose at timet= 0 bit time, A begins transmitting a frame.In the worstcase, A transmits a minimum-sized frame of 512+64 bit times. So A would finish transmitting the frame att= 512 + 64 bit times. Thus, the answer is no, if B’s signal reaches A before bit timet= 512 + 64 bits. Inthe worst case, when does B’s signal reach A?Problem 2Consider a 100 Mbps 100BASE-T Ethernet with all nodes directly connected to a hub. To have an efficiencyof 0.50, what should be the maximum distance between a node and the hub? Assume a frame length of 64bytes and that there are no repeaters. Does this maximum distance also ensure that a transmitting node A
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IP address, Fast Ethernet, 64 bit, 0 bit, 1,000 bytes