Geographic routing with greedy relaying strategies have been widely studied as a routing scheme in sensor networks. These schemes assume that the nodes have perfect information about the location of the destination. When the distance between the source and destination is normalized to unity, the asymptotic routing delays in these schemes are Θ( 1 M(n) ), where M (n) is the maximum distance traveled in a single hop (transmission range of a radio). Three scenarios are considered: (i) where nodes

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... ave location errors (imprecise GPS), (ii) where only coarse geographic information about the destination is available, such as the quadrant or half-plane in which the destination is located, and (iii) where only a small fraction of the nodes have routing information. In this paper, it is shown that even with such imprecise or limited destination-location information, the routing delays are Θ( 1 M(n) ). Further, routing delays of this magnitude can be obtained even if only a small fraction of the nodes have any location information, and other nodes simply forward the packet to a randomly chosen neighbor. Finally, the throughput-capacity is derived for networks with progressive routing strategies that take packets closer to the destination in every step, but not necessarily along a straight-line. Such a routing strategy could potentially lead to spatial "hot spots" in the network where many data flows intersect at a spatial region (a node or group of nodes), due to "sub-optimal" routes with increased path-lengths. In this paper, it is shown that the effect of hot spots due to progressive routing does not reduce the network throughput-capacity in an order sense. In other words, the throughput-capacity with progressive routing is order-wise the same as the maximum achievable throughput-capacity. Subramanian and Shakkottai are with the Wireless