A method and an apparatus for routing data packets. The solution in a communication network including a set of nodes, storing information regarding nodes of the network; and when transmitting a data packet to a destination node in the network, determining and including in the data packet the recipient identification; determining and including in the data packet the direction of the destination node in the network; determining and including in the data packet a hop count indicator indicating the number of node-to-node hops to the destination node; setting in the data packet the transmission direction indicator equal to a value corresponding to direction down and transmitting the packet.