A disconnection-tolerant transport for drive-thru internet environments

Today's mobile, wireless, and ad-hoc communications often exhibit extreme characteristics challenging assumptions underlying the traditional way of end-to-end communication protocol design in the Internet. One specific scenario is Internet access from moving vehicles on the road as we are researching in the Drive-thru Internet project. Using wireless LAN as a broadly available access technology leads to intermittent - largely unpredictable and usually short-lived - connectivity, yet providing high performance while available. To allow Internet applications to deal reasonably well with such intermittent connectivity patterns, we have introduced a supportive Drive-thru architecture. A key component is a "session" protocol offering persistent end-to-end communications even in the presence of interruptions. In this paper, we present the design of the Persistent Connectivity Management Protocol (PCMP) and report on findings from our implementation.