Consider the network shown below. Suppose AS$3$ and AS$2$ are running RIP for their intra$-$AS routing

protocol. Suppose AS$1$ and AS$4$ are running OSPF for their intra$-$AS routing protocol. Suppose eBGP

and iBGP are used for the inter$-$AS routing protocol. Initially suppose there is no physical link between

AS$2$ and AS$4.$

a$.$ Router $3$c learns about prefix $x$ from which routing protocol: OSPF, RIP, eBGP, or iBGP?

b$.$ Router $3$a learns about $x$ from which routing protocol?

c$.$ Router $1c$ learns about $x$ from which routing protocol?

d$.$ Router $1$d learns about $x$ from which routing protocol?

e$.$ Once router $1d$ learns about $x$ it will put an entry $(x,l)$ in its forwarding table. Will I be equal to $I_1$ or

$I_2$ for this entry? Explain why in one sentence.

f$.$ Now suppose that there is a physical link between AS$2$ and AS$4,$ shown by the dotted line. Suppose

router $1d$ learns that $x$ is accessible via AS$2$ as well as via AS$3.$ Will I be set to $I_1$ or $I_2?$ Explain why in

one sentence.

g$.$ Now suppose there is another AS$,$ called AS$5,$ which lies on the path between AS$2$ and AS$4($not

shown in the figure$).$ Suppose router $1$d learns that $x$ is accessible via AS$2$ AS$5$ AS$4$ as well as via AS$3$

AS$4.$ Will I be set to $I_1$ or $I_2?$ Explain why in one sentence.