It is presented a service access apparatus arranged to selectively initiate communication with a network node providing a service. The service access apparatus comprises: a data obtainer arranged to obtain a multilevel hierarchical identifier associated with a user of the service access apparatus and when the multilevel hierarchical identifier does not have a lower level first, reversing the multilevel hierarchical identifier; a concatenator arranged to determine a combined domain name; a domain name lookup client arranged to perform a domain name lookup using the combined domain name, and receiving a response of the domain name lookup; and a communication initiator arranged to, when the response comprises a valid resource record for the network node, initiate communication with the network node using a node pointer in the resource record. A corresponding method, computer program and computer program product are also presented.