Please Show Your Work.

TCP estimates its timeout value based on measurements of packets' round trip time $($RTT$).$ As RTT

increases, the timeout value increases as well. The variability in RTT is also factored into the calculation.

If RTT is a consistent value, the timeout will be closer to the measured RTT$.$ If there is a lot of variability in

$RTT,$ then then timeout will increase. TCP only tracks the RTT of a single packet at a time. When one

ongoing RTT measurement finishes, a new measurement will be started when the next packet is sent.

This means that RTT is not measured for every packet sent. These measurements are then combined

together using a moving average, so as not to give too much weight to any one reading $($which may not

be representative of the current state of the network$).$ The below equations are used by TCP to compute

its timeout value.

EstimatedRTT $T_n=(1-a{)}^{**}$ EstimatedRTT ${?}_{n-1}+a^{**}$ SampleRTT ${?}_n$

$DevRT{T}_n=(1-{)}^{**}$ DevRTT ${?}_{n-1}+{}^{**}|$ SampleRTT ${?}_n-$ EstimatedRTT ${?}_n|$

Timeout ${?}_n=$ EstimatedRTT $n+4*$ DevRTTn

SampleRTT is the most recently measured RTT value. The timeout is updated every time a new

SampleRTT is measured. a and $$ are constants that are used to tune the moving average. Use values $a$

$=0\mathrm{.}1$ and $=0\mathrm{.}25$ for this problem. The below ladder diagram shows several packets traveling back

and forth between two TCP endpoints. Your task is to collect each SampleRTT value TCP would

measure and then update the timeout value accordingly. Report each value you calculate in the

table on the next page.

Note the following:

Show your work $($use additional pages as

needed$).$ To simplify the math, round each

calculated value to the nearest integer.

The highlighted row in the table on the

next page contains the state of the

timeout, estimatedRTT, and devRTT prior

to beginning the problem.

Assume TCP is ready to begin a new RTT

measurement at the start of the problem.

Enough rows are provided to calculate all

the updates to the timeout value that will

occur in the above ladder diagram $($there

may be a few extra rows as well$).$