1.         Terminals A andB are communicating using HDLC protocol in Balanced Mode. Terminal A transmits an HDLC Receive Ready frame indicating thatframe #5 is expected next (that is, a “RR #5”frame). This frame is 6 bytes long. Tell me the value,in binary, of each of the first 3 bytes of this frame. (Youranswer will consist of 24 bits, each being 0 or 1).

2. In aQoS-enabled network with prioritized data, we must use priorityqueues in our routers to implement priority service. Twomethods are used for sending data from these queues: PriorityQueuing (PQ) and Weighted Fair Queuing (WFQ).

a)         Assume that yourrouter has 2 queues – a High Priority (HP) Queue and a LowPriority (LP) Queue. “H” will represent ahigh-priority packet and “L” will represent alow-priority packet. There are currently 6 packets in the HPqueue (“HHHHHH”) and 2 packets in the LP queue(“LL”). Assume that no additional packets arrivewhile these are being sent.

i)          What orderdo these 8 packets get sent out if we are using PriorityQueuing? (Your answer should have 6 “H”s and2 “L”s in it – for example, if your answer is“H H H L L H H H”, that means that 3 HP packets aresent, then 2 LP packets, then 3 HP packets).

              

i)        What order do these 8packets get sent out if we are using Weighted Fair Queuing withweights of 3 and 1 for HP and LP, respectively? (as in part(i), your answer should have 6 “H”s and 2“L”s in it).



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