Link layer support for quality of service on wireless Internet links

We have developed a novel link layer architecture that provides multiple quality of service points simultaneously over wireless Internet links. Our approach enhances the performance of diverse applications over error-prone links. We discuss the performance problems of Internet protocols over wireless links, presenting as a case study our measurements on a wireless LAN, and argue that it is preferable to handle wireless impairments at the link layer. We present a simulation study of various link layer enhancements, and their impact on TCP-and UDP performance. Our results show that different approaches are preferable fur each type of application. We thus propose a multiservice link layer approach that supports multiple link layer mechanisms over a single link. Our scheme is transport protocol-independent and customizable for the underlying wireless link technology. While our approach can be directly deployed on the existing Internet, it also provides support for future QoS-aware protocols and applications. Our simulation results show that our approach uniformly improves the performance of both TCP-and UDP applications.