A method and system for determining an optimal route from a node to a given sink node in a network is described. Sink node periodically transmits routing information containing an indicator of recency. This indicator of recency is periodically updated. Routing information is received by a plurality of nodes in the network. Each node receiving routing information compares the indicator of recency contained in the routing information with an indicator of recency stored at the node to determine whether the received routing information is more recent than the stored routing information. An optimal route to the sink node is determined based on this comparison. Each node also periodically transmits routing information based on stored routing information to other nodes.