Maintaining Router Information

Problem—Routing Loops

Each node maintains the distance from itself to each possible destination network




Slow convergence produces inconsistent routing

Router C concludes that the best path to network 10.4.0.0 is through router B


Router A updates its table to reflect the new but erroneous hop count

Symptom: Counting to Infinity





Packets for network 10.4.0.0 bounce between routers A, B, and C.
Hop count for network 10.4.0.0 counts to infinity.