3.Answer the following questions on router architecture

a)How can packet loss occur at the input port? How can it be eliminated?

b)Describe the situation(s)in which the output queue will build-upat a port.

c)One packet arrives at each of the input ports #5 and #6 exactly at the same time when there areno other packets in the router. Is it possible to forward the packets to output ports #1 and #2, respectively, using a switching fabric of crossbar type?Use a diagram to explainyour answer.[3]

d)If the rate ofthe switching fabric is N times faster than the input line rate,then the queuing delay is negligibly small even if all the packets have to be forwarded to the same output link. But if the rate of the input link and the switching fabric are the same and the packets are to be forwarded to different output ports then what will be the input queuing delay in terms of D, the time to transmit a packets in the following cases:a.Bus based switching fabricb.Crossbar switching fabric?