Systems and methods are provided for routing data through a network. In one system, a first node is enabled to overhear packet transmissions from a second node. The cost of transmitting packets from the first node to the second node is updated based on each overheard packet transmission. In another system, when the cost of transmitting packets from a source to an overhearing node to a destination is less than the cost of transmitting packets from the source to the destination, an advertisement is sent to the source causing the packet transmissions to be routed from the source to the destination through the overhearing node. In yet another system, using a safe-sequence tag that is attached to any packet transmitted by any node and updated when it is received by another node, along with stored histories of best metric advertisements, predetermined rules are applied to maintain loop freedom.