Outline of a centralised multihop ad hoc wireless network

A concept of a multihop ad hoc network and associated algorithms for adaptive clustering in wireless ad hoc networks are presented in this paper. The algorithms take into account the connectivity of the stations as well as the quality of service requirements, The concept of a centralised ad hoc network is adopted, in which a cluster is defined by a Central Controller granting access to the radio interface to all terminals in its cluster. By these means the CC contributes to provide quality of service guarantees to the users. This concept is also used in the HipcrLAN/2 (HL/2) Home Environment Extension (HEE), an ad hoc wireless LAN standardised by the European Telecommunications Standardisation Institute (ETSI). The HEE is restricted to one single cluster. It is shown in this article how the network can be extended over several clusters by the introduction of so-called "forwarding" stations. These forwarders interconnect the clusters and enable multihop connections of users roaming in different clusters. A solution is presented to ensure, as far as possible, an interconnection of clusters by means of the clustering algorithm. (C) 2001 Elsevier Science B.V. All rights reserved.