A method and computer program products for routing a data unit

For routing a data unit through a chain of nodes (101, 102, 103, 104, 105, 106, 10i,..., 10N), the nodes are assigned addresses (1, 2, 3, 4, 5, 6, i, N) that are increasing in one direction of appearance of the nodes in the chain. For routing the data unit, the receiving node (103) first verifies if the destination address of the data unit corresponds with the address (2, 4, 1, 5) of its first hop neighbour (102, 104) or its second hop neighbour (101, 105), and the node (103) routes the data unit directly to its first hop neighbour (102, 104) or its second hop neighbour (101, 105) if this is the case. Otherwise, the node (103) determines the difference between the destination address of the data unit and its own address (3) or the difference between the source and destination address of the data unit, selects a routing direction depending on the sign of this difference, and selects a first hop link (132, 134) when the difference is in magnitude below a threshold value or a second hop link (131, 135) when the difference is above the threshold value.