Demonstrating Active Network Adaptability in Wireless Networks

The IP-based Internet, although wildly successful, is limited in its ability to evolve and adapt, in particular at the network layer. For example, after almost a decade, IP multicast is still not widely available, although applications that might take advantage of its functionality are popular. Mobile/wireless networking is an important emerging area in which adaptivity and evolvability is likely to be especially important due to the widely varying nature of the underlaying communication channels themselves, as well as the rapidly improving understanding of key protocols. We believe that active networking (AN) enables valuable adaptivity that existing technologies currently lack. This is because AN enables, highly flexible packet functionality, on-the-fly protocol deployment, even on a packet-by-packet granularity, and cost-effective network expansion. Because adaptivity and evolvability is at a premium, we have chosen to test our belief in this domain using two case studies: ad hoc routing and TCP over wireless. In our work, we demonstrate AN’s adaptivity by developing a series of designs, simulation studies, and working prototypes. Ad hoc networks are infrastructureless networks in which hosts are typically mobile and must act as routers. Mobility makes routing hard because the state of links changes frequently and routing heterogeneity is likely. In our study, we show how AN can be used to adapt routing to host mobility and traffic activity. We achieve this adaptivity using remote evaluation of active packets, which are good at