In a content addressable network, a hash result of a data item, which is a part of or relating to an entity to be accessed via the network, constitutes (401, 402) at least a part of an L3 network layer, e.g. IP, destination address and/or a protocol layer below L3, e.g. Ethernet, destination address of a protocol data unit, e.g. a data packet, frame, or cell. The entity to be accessed can be e.g. a data file, a hierarchical data structure, or a process to be controlled via the network. There is no need to retrieve e.g. an Ethernet address, or e.g. an IP-address, on the basis of the hash result of the data item, because the hash result itself is used as the address. Hence, in the content addressable network, the step for address retrieval on the basis of the hash result becomes needless.