Problem $2.$ Suppose two hosts, A and B$,$ are separated by $20,000$ kilometers and are connected by a direct

link of $R=2Mbps.$ Suppose the propagation speed over the link is ${2\mathrm{.}5}^{**}{10}^8$ meters $\frac{?}{sec}.$

a$)$ Calculate the bandwidth$-$delay product, $R^{**}{d}_{\text{p}\text{r}\text{o}\text{p}}.$

b$)$ Consider sending a file of $800,000$ bits from Host A to Host B$.$ Suppose the file is sent continuously

as one large message. What is the maximum number of bits that will be in the link at any given time?

c$)$ Provide an interpretation of the bandwidth$-$delay product.

d$)$ What is the width $($in meters$)$ of a bit in the link? Is it longer than a football field?

e$)$ Derive a general expression for the width of a bit in terms of the propagation speed s$,$ the

transmission rate $R,$ and the length of the link $m.$