An efficient transport service for slow wireless telephone links

Modern digital cellular telephones and portable computers have created a new platform for distributed information processing. However, the characteristics of wireless telephone links are different from those of wireline links. With standard TCP/IP protocols, this can lead to severe performance problems; some are related to the control of the wireless link, some to the cooperation of the wireless link and the fixed network. One possible solution is to split the end-to-end communication path into two parts, and to establish a separate control for each part. The Mowgli communication architecture is a sophisticated elaboration of this basic idea covering several data communication layers. One of its main components is the Mowgli data channel service (MDCS), which transparently replaces the standard TCP/IP core protocols over the slow wireless link. We discuss how the Mowgli approach, using the MDCS, alleviates the problems encountered with TCP/IP protocols over slow wireless links. The results of our performance tests indicate the merits of the Mowgli approach. The transfer times and the response times become more stable, transfer times for multiple parallel bidirectional transfers are substantially reduced, and response times in interactive work can be kept at a low and predictable level, even when there is other traffic on the wireless link