Problem E$.$ In the five$-$layer TCP$/$IP protocol stack shown in the graph below, please FILL $1)$ the name of a layer $($e$.$g$.,$ application,

transport, etc.$)$ in the $1$st blank of each question, $2)$ the correct box number$($s$)($i$.$e$.,$ box $1,$ box $2,...,$ box $15)$ in the $2$nd blank of each

question, and $3)$ the name of the data structure $($e$.$g$.,$ message, segment, etc.$)$ in the $3$rd blank, if there is one, of each question.

a$)$ The $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$ layer best corresponds to the phrase: $$passes frames from one node to another across some medium$$; all the

boxes in the above graph that this layer corresponds to are $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$; and the data packets in this layer are called

$\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$s$.$

b$)$ The $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$ layer best corresponds to the phrase: $$handles the delivery of segments from the application layer, may be

reliable or unreliable$$; all the boxes in the above graph that this layer corresponds to are $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$; and the data packets in

this layer are called $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$s$.$

c$)$ The $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$ layer best corresponds to the phrase: $$moves datagrams from the source host to the destination host$$; all the

boxes in the above graph that this layer corresponds to are $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$; and the data packets in this layer are called

$\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$s$.$

d$)$ The $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$ layer best corresponds to the phrase: $$handles messages from a variety of network applications$$; all the boxes

in the above graph that this layer corresponds to are $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$; and the data packets in this layer are called $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$s$.$

e$)$ The $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$ layer best corresponds to the phrase: $$bits live on the wire$$; all the boxes in the above graph that this layer

corresponds to are $\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_.$