$6)$ A communication link uses circuit switching technology to transmit

a message of $5$x$104$ bytes. Assume the length of the line is $100$ km$,$

the velocity of propagation is $108$ m$/$s and the data rate is $100$ Mbps$.$

The maximum efficiency in this case is:

$($a$)580\%($b$)100\%$

$6$

$(($a$)$

$($c$)50\%$

$($b$)$

$($c$)$

$($d$)$ neither a$,$ b or c

$($d$)$

$7)$ Two nodes in a local area network forward frames of $1000-$bits.

The propagation time between the two nodes is $2$ times the

transmission time.

If the two stations use stop$-$and$-$wait, what will be the maximum line

efficiency?

$($a$)50\%$

$($b$)1000$

$7\mathrm{.}1$

$($a$)$

$($b$)$

$($c$)100\%$

$($C$)$

$($d$)1\%$

$($d$)$

In this case if the two stations use sliding window protocol, the

maximum line efficiency will be up to:

$($a$)100\%($b$)10\%$

$($c$)90\%$

$($d$)1$

$7\mathrm{.}2($a$)$

$($b$)$

$($c$)$

$($d$)$