NeTS-NBD: Towards a Disconnection-Tolerant, Opportunistic Internet

Rensselaer Polytechnic Institute, Troy NY

Investigators

Abstract

This project considers broadening the reach of the Internet by extending it to support large-scale disconnection tolerant and opportunistic connectivity. Such networks are called DTNs or DTONs. This paradigm extension is valuable for: airborne/automobile, rural/wilderness and emergency/wartime DTNs. Current networking protocols are optimized to function when networks are connected most of the time, and disconnected rarely. This project systematically explores situations where disconnection is the norm, and connectivity between nodes/clusters is opportunistic. Intellectual merit. Since structure is hard to maintain in DTONs, the project uses unstructured building blocks. The fundamental problem of routing is accomplished using efficient, unstructured methods, primarily random walks. While unstructured methods work well in special underlying graph structures, it is an open problem of how to use unstructured search for point-to-point connectivity (equivalent to "needle-in-a-haystack" indirections). DTONs are modeled using a new combinatorial object: time-evolving graphs represented algebraically as tensors. The actual protocols for random walks are biased using the new notion of weak-state that is learned locally or disseminated globally. Information-theoretic techniques are used to develop bounds for network goodput and overhead. Broader impact includes DTON applications across a variety of dynamic networks such as highway traffic management and biological systems. The economic and social impacts of extending the reach of the Internet to airborne, wilderness and infrastructure-free locations are immense. The PIs are disseminating preliminary formulations of such ideas to the industry and national laboratories. The PIs integrate material across their courses, and operate a novel weblog (blog) for the project for broader dissemination.