Consider the network shown below. Suppose AS3 and AS2 are running OSPF for their
ID: 3707049 • Letter: C
Question
Consider the network shown below. Suppose AS3 and AS2 are running OSPF for their intra-AS routing protocol. Suppose AS1 and AS4 are running RIP 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 AS2 and AS4.
a. Router 4c learns about prefix x from which routing protocol: OSPF, RIP, eBGP, or iBGP?
b. Router 3b learns about x from which routing protocol?
c. Router 1a learns about x from which routing protocol?
4b AC 4a AS4 2c 3C 2 a 2b 3b 1 b AS2 1a AS3 1d AS1Explanation / Answer
eGBP :----external BGP runs between routers in different ASs.
iGBP :---- internal BGP runs between routers in same AS.
a. Router 4c learns about prefix x from which routing protocol?
Answer:---- eBGP
b. Router 3b learns about x from which routing protocol?
Answer:---- iBGP
c. Router 1a learns about x from which routing protocol?
Answer:--- iBGP
d. Router 1c learns about x from which routing protocol?
Answer:--- eBGP