Enhancing IP service provision over heterogeneous wireless networks: A path toward 4G

Second-generation mobile radio systems have been deployed successfully worl dwide and have evolved to higher data rates and services. Third-generation mobile radio systems are currently starting to be developed in different re gions of the world. Today, the open question is how the third-generation sy stems will evolve. It is very likely that fourth-gene ration systems will n ot be a single standardized air interface, but a set of different technolog ies and standards. In particular, wireless LAN/wireless PAN type systems ar e designed for high/medium-data-rate access, low range, and, in general, lo w mobility. They are applicable to corporate networks and public access as a complement to cellular mobile radio systems for hot spot applications suc h as airports, hotels, and campuses. In this specific WLAN/WPAN framework a nd to guarantee an agreed QoS provision over such infrastructures, we propo se a solution based on the wireless adaptation layer approach. In particula r, aspects related to wireless link impairments and traffic requirements ar e approached by the implementation of configurable, modular software that i s adapted to the specific conditions and needs of the particular wireless i nfrastructures.