This elementary problem begins to explore propagation delay and transmission delay, two central concepts in data networking. Consider two hosts, A and B$,$ connected by a single link of rate R bps$.$ Suppose that the two hosts are separated by m meters, and suppose the propagation speed along the link is s meters$/$sec$.$ Host A is to send a packet of size L bits to Host B$.$

Express the propagation delay, dprop, in terms of m and s$.$

Determine the transmission time of the packet, dtrans, in terms of L and R$.$

Ignoring processing and queuing delays, obtain an expression for the end$-$ to$-$end delay.

Suppose Host A begins to transmit the packet at time t $=0.$ At time t $=$ dtrans, where is the last bit of the packet?

Suppose dprop is greater than dtrans. At time t $=$ dtrans, where is the first bit of the packet?

Suppose dprop is less than dtrans. At time t $=$ dtrans, where is the first bit of the packet?

Suppose s $=2\mathrm{.}5*108$ mps$,$ L $=120$ bits, and R $=56$ kbps$.$ Find the distance m so that dprop equals dtrans.