RIPv1

RIP is an interior gateway protocol (IGP) that uses a distance-vector algorithm to determine the best route to a destination, using the hop count as the metric. RIP version 1 (RIPv1) uses broadcast packets that contain the minimal information necessary to route packets through a network. Also, RIPv1 does not support authentication, triggered updates (just periodic updates are supported), variable-length subnet mask (VLSM), and discontinuous networks.