QUESTION $1$

$($a$)$

$[8$ Marks$]$

Consider the network depicted above. With reference to the TCP$/$IP network model,

and using bullet points, explain the steps involved in the creation of an ICMP echo

request $($i$.$e$.$ a ping$)$ at $10\mathrm{.}10\mathrm{.}10\mathrm{.}11$ and its transmission to $172\mathrm{.}16\mathrm{.}13\mathrm{.}32.$ Include in

your answer an outline of the role, if any, played by supporting protocols and routing

tables. Assume all ARP caches start empty and document any assumptions.

$($b$)$

$[7$ Marks$]$

Consider the network depicted above. Explain how an attacker at $192\mathrm{.}168\mathrm{.}3\mathrm{.}21$

would go about intercepting all traffic between $192\mathrm{.}168\mathrm{.}3\mathrm{.}33$ and the $172\mathrm{.}16\mathrm{.}0\mathrm{.}0/16$

network. Mention any relevant tools in your explanation.

$($c$)$

$[5$ Marks$]$

Consider the network depicted above. With reference to the TCP$/$IP network model,

and using bullet points, explain what happens when $172\mathrm{.}16\mathrm{.}12\mathrm{.}31$ pings

$172\mathrm{.}16\mathrm{.}14\mathrm{.}33($note there is no device with the latter IP address$).$ Include in your

answer an outline of the role, if any, played by supporting protocols and routing

tables. Assume all ARP caches start empty and document any assumptions.

$[$END OF QUESTION $1]$