Rerouting stands for alternative or substitute route. Rerouting is performed by routers or switches when these components detect an overload or an interruption on the planned route, when a node has failed or a congestion situation has occurred.
The routers choose a completely new alternative route in case of overload or interruptions, which is independent of the existing routing tables. Rerouting also exists as a telecommunications service in call forwarding. In these services, depending on the state of the receiving station, calls are divided into: general call forwarding( CF), call forwarding on busy( CFB), call forwarding and call forwarding( CD) and call forwarding on no answer( CFNR).