Abstract
Many ad ho network protools and appliations assume the knowledge of geographi loation of nodes. The absolute loation of eah networked node is an assumed fat by most sensor networks whih an then present the sensed information on a geographial map. Finding loation without the aid of GPS in eah node of an ad ho network is important in ases where GPS is either not aessible, or not pratial to use due to power, form fator or line of sight onditions. Loation would also enable routing in suÆiently isotropi large networks, without the use of large routing tables. We are proposing APS { a distributed, hop by hop positioning algorithm, that works as an extension of both distane vetor routing and GPS positioning in order to provide approximate loation for all nodes in a network where only a limited fration of nodes have self loation apability.