Title:
Delay Tolerant and Opportunistic Networks

Date:
23-Feb-2009

Speaker:
Prof. Jon Crowcroft

Affiliation:
University of Cambridge

Biography:
Jon Crowcroft is the Marconi Professor of Networked Systems in the Computer Laboratory, of the University of Cambridge. Prior to that he was professor of networked systems at UCL in theComputer Science Department. He is a Fellow of the ACM, a Fellow of the British Computer Society and a Fellow of the IEE and a Fellow of the Royal Academy of Engineering, as well as a Fellow of the IEEE. He was a member of the IAB 96-02, and went to the first 50 IETF meetings; was general chair for the ACM SIGCOMM 95-99. He has published 5 books - the latest is the Linux TCP/IP Implementation, published by Wiley in 2001. He is the Principle Investigator in the Computer Lab for the EU Haggle Project in DTN, and the EU Social Networks project, the EPSRC TINA project on location sensors and wireless networking of airports, and for the ITA project in next generation wireless networks. Industrial Experience Worked for Bloomsbury Computer Consortium for 2 years. Sabbatical at Hewlett Packard Research Labs Bristol Technical Advisory Board for 10 startups (Ensim, Orchestream, Bandwiz, Nexthop, Interprovider, Corvil, Ethos, Hidden Footprints and others). On Technical Advisory Board for Microsoft ResearchCambridge, and MPI, and previously for DoCoMo Labs, California and visiting faculty at Intel research. Technical reviewer for corporate datanetwork stratetgy, Ericsson Consulting to Reuters, BBC, Nortel, Cisco, Oftel (now Ofcomm) amongst others. Research Interests Communications and Multimedia Systems, but especially Internet related. Currently on Sabbatical at IMDEA Networks, Madrid.

Further information:
http://www.cl.cam.ac.uk/users/jac22/

Venue:
Cole 0.35 MSc Lab

Abstract:
We are so used to networks that are "always there", so called infrastructural networks such as the phone system, Internet, the cellular (GSM, CDMA, 3G) and so on that we forget that once upon a time (why, only in the 1970s) computer communications was fraught with problems of reliability, and challenged by very high cost (or availability) of connectivity and capacity. One we had UUCP and E-Mail, which predate any of today's infrastructures, but coped very well with these challenges. Now, it appears that it is worth revisiting these ideas for a variety of reasons: it looks like we cannot afford to build a Solar System wide Internet just yet; it looks like one can build effective end-to-end mobile applications out of wireless communication opportunities that arise out of infrequent and short contacts between devices carried by people in close proximity, and then wait til these people move on geographically to the next hop; it is interesting to speculate that these systems may actually have much higher potential capacity than infrastructural wireless access networks, although they present other challenges (notably higher delay). This set of talks will be about the last 10 years of work leading up to our current understanding of how to build Delay Tolerant and Opportunistic Networks, and how to model their performance.

Programme:
10.00 – 11.00 Lecture 1: Delay Tolerant Networking - it really is rocket science.
Room 0.35
(Jack Cole Building)
In this lecture we review the DTN work over the last 10 years, starting from the origins as an initiative to provide a commodity network system for the planned manned mission to Mars, and ending up with an architecture for any network that is challenged by frequent disruptions, from oceanographic sensing, to disaster relief communications when everything else has failed, and on to building useful services in places where the population cannot (yet) afford an infrastructure.
11.00 – 11.30 Coffee
Coffee Room
(Jack Cole Building)
Coffee & Tea with Biscuits 11.30 – 12.30 Lecture 2: Opportunistic Networking - Making people network.
Room 0.35
(Jack Cole Building)
4 billion people have cell phones. Most have not just a radio for voice communication, but also a bluetooth, short range radio which allows devices to communicate directly (without involving a cell tower). Increasingly, devices also have WiFi which can also be used without any recourse to a provider. We can build networks that use encounters between devices carried by people, and then use the natural mobility of humans (walking, cycling, driving, in trains, planes etc) to carry stored data to the next hop. Such systems can be used in a wide variety of scenarios for disaster communication when the infrastructure is broke, for networks in developing regions (or out in the middle of the ocean, or in space) where there isn't any infrastructure anyway, and for applications which may enjoy high capacity, but do not mind higher (or even uncertain) delays. In the process of designing and building such systems, we may accidentally (on purpose) design systems tat simply work better in the now more traditional setting of the Internet, but cope more seamlessly with the occasional glitches that show up there. We may find it easier to build applications on such systems that tolerate occasional (or frequent) disruptions. One interesting synergy I will touch on here is that applications for opportunistic networks often entail unspecified sender or recipient (i.e. they are data dissemination applications) which resemble some of the new ideas in Data Oriented networking in the Internet. At the same time as resource pooling and multipath routing, and interest-based delivery are being explored for the Internet to support this, such approaches have already proved natural in designing data forwarding schemes in Opportunistic Networks. We'll look at one such protocol.
14.30 – 15.30 Lecture 3: How much delay must I tolerate in my DTN/Oppnet?
Room 0.35
(Jack Cole Building)
It turns out that we have a wealth of data emerging from measurement made by wireless networking researchers (e.g. on Crawdad) but also increasingly of interest to social scientists (anthropologists trying to understand human society) and medical researchers (epidemiologists trying to understand the spread and evolution of diseases).
In this final part of the lecture, I will look at the emerging models we have both for delivery success and delay, and for capacity of DTNs.

Generic information:
You can find the video clips related to this lecture series by following the link https://studres.cs.st-andrews.ac.uk/Library/DistLec/2009-1/. (you have to be in the school to access them)