Department for Electrical and Communications Engineering

Networking Laboratory

S-38.3151 Delay-tolerant Networking (DTN) - 3 ECTS

News

• 18.10.2007: Java API for DTN2 can be found here
• 17.10.2007: Latency measurement added to dtnrecv. Replace your old version with this and re-run make.
• 11.10.2007: Deadline for assignment 1 extended to Friday 19.10.2007, 23:55.
• 10.10.2007: Use this version of dtnrecv if you're getting xdr errors. Also found in /p/edu/s-38.3151/assignments/dtnrecv.c.
• 4.10.2007: Disk space is available for assignment 1 for those who have sent us their group members. See Assignment 1 below
• 2.10.2007: Please inform us whether you're doing assignment 1 alone or your group members if you're in a group
• 1.10.2007: Deadline for assignment 1 is Friday 12.10.2007 at 23:59
• 1.10.2007: New articles added to the materials

Overview

DTN is an emerging research area that takes a different approach to (inter)networking and allows to work in stressed as well as in highly heterogeneous environments. DTN features a number of unique properties which make this concept applicable to challenged networking environments in which traditional communication paradigms would fail or perform rather poorly: DTN uses only communication based upon asynchronous messaging, does not rely on the existence of an end-to-end path at any point in time, and combines store-and-forward message delivery with physical data carriage. DTN technologies may be applied for challenged static network setups (including, for example inter-planetary or underwater communications) but is also applied to (sparse) mobile ad-hoc networks to enable communications. Deterministic and/or probabilistic routing mechanisms are applied depending on the respective environment. This course will introduce the fundamentals of this relatively young research are and explore some specific aspects in (practical) assignments.

The course will combine lectures with assignments (2 practical, 1 theoretical).

Contact

For questions concerning the course, please use the Newsgroup opinnot.sahko.s-38.tietoverkkotekniikka or send mail to

• Teemu Kärkkäinen <teemuk (at) netlab.tkk.fi>
• Jörg Ott <jo (at) netlab.tkk.fi>

Lectures and exercises

Lectures will be held: Monday 10 - 12 (I346) and Tuesday 12 - 14 (I346).

The lectures, exercises, and the exam will in English language.

Requirements and grading

To pass the course, the two or three assignments must be completed and the written exam must be passed.

Assignment 2

• 130.233.154.182:8550
• 130.233.154.182:8551

• 130.233.154.182:8660
• 130.233.154.182:8661

Assignment 1

• 130.233.154.182:5556
• 130.233.154.182:5558

There is disk space available for use with this assignment at /p/edu/s-38.3151/assignments/. To get access to this space you will have to inform us whether you're doing the assignment alone or the members of your group. Please include your computer center username.

To use this space:

• Check that you're a member of a-s38dtn group: group list. If you're not, you need to send us your computer center username.
• Create your own directory under /p/edu/s-38.3151/assignments/. E.g., /p/edu/s-38.3151/assignments/myname
• Set the access rights so that only the owner of the folder can access the contents with the command chmod 0700 /p/edu/s-38.3151/assignments/myname
• Copy your work into the directory.

Hints:

• When running multiple instances of dtnd on the same machine the environment variable DTNAPI_PORT can be used to control which dtnd instance the applications connect to. I.e., start each instance of dtnd with "env DTNAPI_PORT=[port number] ./dtnd ..." with a different port number. Then start the application similarly with "env DTNAPI_PORT=[port number] ./dtnping ..." where the port number matches the port number of the dtnd instance you want the application to connect to.

• dtnrecv currently always claims 0ms delay for all bundles. We're looking into fixing this.

Time Table

Material

The lecture material (slides) will be available in digital format (PDF) from this web page.

As DTN is a new field of research, there is only one book on the topic. You may purchase this book, but all the required material for the course will be available on the slides and in research papers.

The book

• Stephen Farrell and Vinny Cahill: "Delay- And Disruption Tolerant Networking" Artech House, 2005. ISBN 1-59693-063-2

RFCs and Internet-Drafts

• Delay-Tolerant Networking Architecture
• Bundle Protocol Specification
• Delay-Tolerant Networking Security Overview
• Bundle Security Protocol Specification

Articles

Architecture:

• A Delay-Tolerant Network Architecture for Challenged Internets - Kevin Fall

• Routing Strategies for Delay-Tolerant Networks - Evan P.C. Jones and Paul A.S. Ward
• Routing in Intermittently Connected Mobile Ad Hoc Networks and Delay Tolerant Networks: Overview and Challenges - Zhensheng Zhang
• Routing in a Delay Tolerant Network - Sushant Jain, Kevin Fall, and Rabin Patra
• Practical Routing in Delay-Tolerant Networks - Evan P.C. Jones, Lily Li, and Paul A.S. Ward
• Epidemic Routing for Partially-Connected Ad Hoc Networks - A. Vahdat and D. Becker
• Probabilistic Routing in Intermittently Connected Networks - A. Lindgren, A. Doria and O. Schelén

• [mandatory] Multicasting in Delay Tolerant Networks: Semantic Models and Routing Algorithms - Wenrui Zhao, Mostafa Ammar, and Ellen Zegura
• [mandatory] Delay-Tolerant Broadcasting - Gunnar Karlsson, Vincent Lenders, and Martin May
• Opportunistic Content Distribution in an Urban Setting - Jérémie Leguay et al.

• Applicability of Identity-Based Cryptography for Disruption-Tolerant Networking - N. Asokan et al.
• Security Considerations in Space and Delay Tolerant Networks - S. Farrell and Vinny Cahill
• Also see the security related internet drafts above

• Application Protocol Design Considerations for a Mobile Internet - Joerg Ott