P$-3.$ Consider the network shown below. Suppose AS$3$ and AS$2$ are running OSPF for their

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

rotocol. Suppose eBGP and iBGP are used for the inter$-$AS routing protocol. Initially suppose

there is no physical link between AS$2$ and AS$4.$

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

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

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

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