This paper presents a Secure Destination-Sequenced Distance-Vector (SDSDV) routing protocol for mobile ad hoc wireless networks. The proposed protocol is based on the regular DSDV protocol. Within SDSDV, each node maintains two one-way hash chains about each node in the network. Two additional fields, which the authors call AL (ALteration) field and AC (ACcumulation) field, are added to each entry of the update packets to carry the hash values. With proper use of the elements of the hash chains, the sequence number and the metric values on a route can be protected from being arbitrarily tampered.