Virtual Private Network

N$8\mathrm{.}2.$ To $log$ into SIUC's network, Bob needs to use a TLS$-$based VPN$.$ After he has

established a VPN tunnel between his machine and SIUC's network

$(128\mathrm{.}230\mathrm{.}0\mathrm{.}0/16),$ he checks the routing table on his computer. Here is what he

sees:

From the above routing information, please answer the following questions $($you need

to explain your answer$).$

$($a$)$ What is the IP address of the TUN interface on Bob's machine?

$($b$)$ What is the IP address of SIUC's VPN server?

$($c$)$ What is the computer's real IP address, i$.$e$.,$ the IP address assigned to the

machine's physical network interface card?

$($d$)$ Assume that Bob is behind a firewall that blocks him from accessing a web site

$($assume that the IP address of the web site is $1\mathrm{.}2\mathrm{.}3\mathrm{.}4).$ Please describe how Bob

can use SIUC's VPN to bypass the firewall. If changes need to be made to this

routing table, please show exactly what changes Bob needs to make to achieve

the goal.

N$8\mathrm{.}3.$ In Figure $1,$ Machine $x$ has established a VPN with Machine $Y,$ which is a VPN

server connected to the private network $10\mathrm{.}0.\frac{20\mathrm{.}0}{24}.$ With the VPN$,$ a user on

Machine X can now access machines on the $10\mathrm{.}0\mathrm{.}20\mathrm{.}0/24$ network. The user

runs the following command on Machine X: "telnet $10\mathrm{.}0\mathrm{.}20\mathrm{.}100".$ Figure $1$

shows the packet flow triggered by this command. Please answer the following

questions:

$($a$)$ What is the relationship between packets $1$ and $2?$

$($b$)$ What is the relationship between packets $3$ and $4?$

$($c$)$ What is the source IP and destination IP of packets $1,2,3,$ and $4?$