|  | 11.3 | Distance-Vector Routing
| 11.3.6 | The solution of defining a maximum
Distance-vector routing algorithms are self-correcting, but a routing loop problem can require a count to infinity first. To avoid this prolonged problem, distance-vector protocols define infinity as a specific maximum number. This number refers to a routing metric (e.g. a simple hop count). With this approach, the routing protocol permits the routing loop to continue until the metric exceeds its maximum allowed value. The graphic shows the metric value as 16 hops, which exceeds the distance-vector default maximum of 15 hops, and the packet is discarded by the router. In any case, when the metric value exceeds the maximum value, Network 1 is considered unreachable.