10.4 Perspectives and Conclusions

Among local wireless access technologies, WLANs have a predominant place in the market, as they are increasingly replacing wired LANs as the method of choice for accessing the Internet. By far, the most popular WLAN technology is currently 802.11 (particularly the 802.11b variation, also named Wi-Fi). Wireless technologies allow hosts to freely roam between cells, but the Internet's core protocols were not designed with mobility in mind. Even though Mobile IP has been proposed as a solution to handle IP mobility, it is not very suitable for the case of micro-mobility (i.e., mobility within a very limited geographical span). Thus, IP micro-mobility protocols have been proposed.

Recent research has addressed the problem of providing QoS guarantees in micro-mobility environments. Some have proposed RSVP-like signaling protocols to make resources reservations, ^[35] while others have taken the differentiated services approach (proposed by the IETF), where no hard QoS guarantees are provided, but only statistical guarantees. ^[36] Also, work in progress within the IETF's SeaMoby Working Group is currently addressing problems related to QoS in mobile environments, although not exclusively for the case of micro-mobility.

^[35]Legrand, G., Qualit de Service dans les Environnements Internet Mobile, Ph.D. thesis, Universit Pierre et Marie Curie, Paris VII, July 2001.

^[36]Garc a-Mac as, J.A. et al., Quality of service and mobility for the wireless Internet, in ACM/IEEE Mobicom 2001, Workshop on Mobile Internet (WMI), Rome, Italy, July 2001.