Suppose a network N within a larger organization A acquires its own direct connection to an Internet service provider, in addition to an existing connection via A. Let R1 be the router connecting N to its own provider, and let R2 be the router connecting N to the rest of A.

(a) Assuming N remains a subnet of A, how should R1 and R2 be configured? What limitations would still exist with N’s use of its separate connection? Would A be prevented from using N’s connection? Specify your configuration in terms of what R1 and R2 should advertise and with what paths. Assume a BGPlike mechanism is available.

(b) Now suppose N gets its own network number; how does this change your answer in (a)?

(c) Describe a router configuration that would allow A to use N’s link when its own link is down.