Consider the network shown below which contains four IPv$6$ subinets, connected by a mix of IPv$6-$only routers $($shaded blue$),$ IPv$4-$only routers $($shaded red$)$ and dual$-$capable IPv$6/$IPv$4$ routers $($shaded blue with red interfaces to IPv$4$ routers$).$

Suppose that a host of subnet F wants to send an IPv$6$ datagram to a host on subnet D$.$ Assume that the forwarding between these two hosts goes along the path: $FbcaCA$

a$.$ Is the datagram being forwarded from F to b an IPV$4$ or IPV$6$ datagram?

IPv$4$

IPv$6$

b$.$ What is the source address of this F to b datagram?

In an RSA system, the public key $(n,e)$ of a given user is $(247,11).$

a$.$ What is the value of the exponent in the private key $(n,d),$ of this user?

b$.$ Suppose you want to send this user the message $m=35,$ write down the expression to generate the ciphertext for this message.

$$

c$.$ Suppose that your ciphertext, c$,$ is $48,$ write down the expression to generate the plaintext matching this ciphertext.

d$.$ Can you encrypt the message $m=248$ with this public key?

a$.$ Yes

b$.$ NO