Our contribution in this paper focuses on cluster creation, addressing mechanism and autorouting. Actually, we propose an address assignment mechanism, using node clusters. These multi-hop clusters are trees with a given depth al lowing to automatical ly assign addresses. We designed a new multi-hop performance criterion (we want the cluster head to have large degree). This address assignment mechanism is designed for wireless fixed sensor networks, which is usual ly the case for sensor networks, where self-organisation is crucial. Because of its scalability, it is particularly suitable for very large sensor networks, where automatic address assignment cannot be avoided. It is a completely distributed node al location address, with no possible duplication. Moreover, it has the nice feature to al low autorouting. Actual ly, like in Banyan switching networks, we use a systematic pattern to assign the addresses, which can be used for autorouting by deriving local ly on a node the next node on the root without the help of any routing protocol