Enabling Multihop Communication in Spontaneous Wireless Networks
Résumé
Although so far not as successful as managed wireless networking, an alternative type of wireless networks has also emerged since 2000: spontaneous wireless networks. Inspired by the Push-To-Talk concept used in walkie-talkies (portable half-duplex radio transceivers developed during the Second World War), spontaneous wireless networks depart from the traditional distinction between router and hosts, whereby each user terminal (hereafter, node) may behave as a router and a host simultaneously. In spontaneous wireless networks, user terminals are thus ''prosumers" (i.e. both producers and consumers) of networking resources instead of mere consumers. Terminals self-organize to provide multi-hop wireless communications among themselves, with or without help/control from infrastructure devices. Each node may thus simultaneously originate/receive traffic (role of a host), as well as forward traffic on behalf of other terminals (role of a router). Popular examples of spontaneous wireless networks include mobile ad hoc networks, wireless mesh networks, wireless sensor or actuator networks, wireless smart meter networks, vehicular networks, opportunistic wireless networks or delay tolerant networks. Popular link layer technologies providing device-to-device communication in spontaneous wireless networks include so far IEEE 802.11 ad hoc mode and IEEE 802.15.4. However, in order to provide multi-hop communication in spontaneous wireless networks, additional techniques have to be employed on top of such link layer technologies, and that is the subject of this chapter. The focus is put on the use of standard IP protocols to enable multi-hop wireless communications in spontaneous wireless networks - in order for these networks to effectively blend in the Internet, where appropriate.