Transmitting a $9000$ byte message from A to C

$($a$)$ How many pack needed, with each packet requirility to fragment the message into as

time of the packets will you create from the message in additional $40-$byte header.

$($b$)$ If node A starmplete message from $A$ to $C?$

time at which nods transmission of the first packet at time $t=0,$ calculate the $($minimum$)$

Note that A sends out the $C$ receives the full message.

has to receive the complata dackets sequentially without waiting for the ACK from B$,$ and B

ignore processing and

$($use transmission and propagation delays only$)$

$\{$Hint: Assume that you fragment the $9000-$byte message into $x$ equal$-$size packets. Find an

expression $f(x)$ for the reception time at $C$ of the last packet of the message in terms of the

transmission time $T(x)$ of each packet and the link propagation delay $P,$ and minimize $f(x)$ to

obtain the optimum value of $x$

packer six $=\frac{9000-40x}{x}=\frac{9000}{x}-40$

Transnission time $t=\frac{\text{p}\text{a}\text{c}\text{k}\text{e}\text{t}\text{s}\text{i}\text{z}\text{e}8}{1000{10}^6}=\frac{9-0\mathrm{.}32x}{x{10}^6}$

$T(x)=3t+2p=(\frac{27-0\mathrm{.}96x}{x}+1)+rs=(\frac{27}{x}+0\mathrm{.}04)$