Question :
Suppose 4 packets of a message, each of L bits arrive at a switch (router) and traverse a link with rate R bps to the destination.
Further, suppose that the link is free when the first packet arrives, and the second packet arrives when the first packet is half way through its transmission, and the third packet arrives just after the first packet completes its transmission.
Compute the total delay (queuing + transmission) of the message (from the switch (router) to destination).