Source routing allows the originator of a packet to partially or completely specify the path that a packet will take through a network, as well as the return path. In contrast, non-source-routing devices determine that path based on the packet’s destination. Source routing allows:
Source routing requires careful management by the administrator when building the source address selection and source routing tables to ensure a coherent overall routing strategy. For this reason, it is often called policy routing, since routing behavior is determined by a collection of routing tables built by the administrator.