Using circuit switching, how many bits need to be transmitted to

transmit this message over the two hops.

$($a$)6$ Mbits $($b$)2$ Mbits $($c$)1$ Mbits $($d$)3$ Mbits

$10\mathrm{.}3($a$)$

$($b$)$

$($c$)$

$($d$)$

Using packet switching of $105$ bit packets with a $1000$ bit header, hor

many bits need to be transmitted?

$($a$)$

$1\mathrm{.}11$ Mbits $($b$)1$ Mbits $($c$)1\mathrm{.}01$ Mbits $($d$)2\mathrm{.}22$ Mbits

$10\mathrm{.}4($a$)$

$($b$)$

$($c$)$

$($d$)$

$11)$ Two stations $($A$)$ and $($B$)$ use selective$-$reject ARQ to exchange

frames of $100$ bits at a data rate of $10$ Mbps$.$ The two stations are

connected by a full duplex line of $10$ km long. Assume the velocity is

$108$ m$/$s and a BER$=5$x$104.$

The window size to achieve an efficiency of $80\%$ is:

$($a$)18$

$($b$)$

$17$

$($c$)$

$17\mathrm{.}68$

$($d$)17\mathrm{.}684$

$11\mathrm{.}1($a$)$

$($b$)$

$($c$)$

$($d$)$