Question $2$

A system using the Stop$-$and$-$Wait ARQ protocol has the following characteristics:

Distance between sender and receiver: $5000m$

Propagation speed: $2{10}^{8}m{s}^{-1}$

Data rate: $10Mbps$

Overhead for each frame $($header $+$ trailer$)$: $100$bits

Processing delays and ACK transmission time are ignored

Carrier Sense Multiple Access with Collision Detection $($CSMA$/$CD$)$ is used

$($a$)($i$)$ What is the propagation time from the sender to the receiver?

$(2$ marks$)$

$($ii$)$ What is the relationship between the minimum frame size and the proper operation for CSMA$/$CD networks in a system? Explain briefly.

$(2$ marks$)$

$($iii$)$ Hence, what is the MINIMUM frame size for this system? Express your answer in bits. $(2$ marks$)$

$($iv$)$ For each frame in $($iii$),$ what is the MINIMUM data size? Express your answer in bits. $(1$ mark$)$

$($v$)$ Suppose the Ethernet MAC sublayer of the sender in this system receives $100$ bits of data from the upper layer, and the data has to be sent immediately. What happens to the data field of this Ethernet frame?

$(1$ mark$)$

$($b$)$ Suppose each frame in the above network carries $1000$ bits of data and there are totally $2,000,000$ bits of data to be sent.

$($i$)$ How many frames will be sent?

$(1$ mark$)$

$($ii$)$ What is the transmission time for each frame?

$(2$ marks$)$

$($iii$)$ Assume no frame is lost or damaged. What is the total time to transmit all the data?

$(3$ marks$)$

$($iv$)$ Assume there is ONE data frame lost in every $20$ data frames sent, and there is no loss if less than $20$ frames sent. What is the total number of lost frames?

$(3$ marks$)$

$($v$)$ If the timeout value is $500s,$ what is the total time required to send all the data?

$(3$ marks$)$