The count to infinity problem is associated with
The count to infinity problem is associated with
Answer : Distance Vector Routing Protocol
Explanation:Distance-vector protocols are based on calculating the direction and distance to any link in a network. "Direction" usually means the next hop address and the exit interface.
The Distance-vector protocols does not prevent routing loops from happening and suffers from the count-to-infinity problem.
An example would if Router 2's link to Network A is via Router 1's link i.e. R2 has learned about a route to network A from R1 initially.
If Router 1's link to network A fails, R1 will update its routing table immediately to make the distance 16 (infinite). In the next broadcast, R1 will report the higher cost route. Now suppose r2 advertise a route to Network A via R1 in its normal advertisement message, just after R1’s connection to network A fails. If so R1 will receive this update message and sees that Router 2 has a two-hop link (which is actually via Router 1) to Network A, according to the normal vector-distance algorithm it will install a new route to network A via R2, of length 3.
After this, it would began advertising it has a three-hop link to Network A and
then route all traffic to Network A through R2. This would create a routing loop, since when Router 2 (R2) sees that Router 1 get to Network A in three hops, it alters it own routing table entry to show it has a four-hop path to Network A.This is known as Count-to Infinity problem, i.e. bad news travel slowly through the network and to advertise a bad news throughout the entire network will take a long time.This problem is also called as slow convergence problem.In the next section we shall discuss some of the possible solutions to this slow convergence problem
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