Uppsala universitet

Projektuppgifter i Datakommunikation II

Vi erbjuder kursdeltagarna att göra ett projekt istället för en uppsats. Projektet innebär programmering och sökning av information samt en demo/presentation av projektet. Varje projekt består av ett team om 3-5 personer. Ni organiserar er själva inom teamet och lägger upp en projekt- och tidsplan som diskuteras med er handledare. Omfattningen av projektarbetet ska inte omfatta mer än uppsatsarbetet (1-3 veckor beroende på kursvariant) även om det är lätt att lägga ner betydligt mer tid på uppgiften.

Varje projekt tilldelas en handledare, en doktorand eller lärare, som bistår med kunskap och praktiska arrangemang samt ser till att allt löper enligt plan. Alla projekten har någon anknytning till den forskning som bedrivs inom området vid institutionen.

Projekten redovisas den 26 maj med företrädesvis en demo och en presentation av resultatet. Varje projekt tilldelas 30 minuter.

Ett projektrum finns till förfogande: Konferensrummet, plan 3, Hus 7 ("Bastuhuset"). Dörrkoden lämnas av handledaren.

Följande projekt erbjudes vt 2003:

  1. *Extended functionality in Explanograms
  2. *Peer-to-Peer networking. Testbed port and benchmarking.
  3. *Ad hoc network (APE) measurements
  4. WLAN Authentication server for students at Uppsala University
  5. *Security Proxy for Limited Devices
  6. Energy saving by using play-out buffers on thin clients
  7. Vertical handover between Bluetooth - GPRS

Stjärnmarkerade projekt är lämpliga som utökade DV/MN projekt.

Med rött markerade ämnen är bokade.


Varje grupp bedöms utifrån tre kriterier:

  • Genomförande av uppgiften
  • Presentation och demonstration

Alla deltagarna måste vara delaktiga i både projektets genomförande och presentation för att betyget godkänt skall ges. Ett bra projekt kan höja slutbetyget. En mindre bra insats kan däremot inte sänka tentamensbetyget. Observera att projektet måste slutföras under kursen gång och att det inte kan examineras vid ett senare tillfälle.


Title: Extended functionality in Explanograms

Suitable for: 6  DV/MN  - students


An explanogram is a web based animated presentation of multi-media enhanced written notes. The technique uses a Bluetooth enabled pen and a special patterned paper to record timestamped penstrokes and automatically transfer them to a database server via the Internet. Using this data an animated representation of what was written on the paper can automatically be generated and presented in a web page.

The project will extend this basic functionality allowing audio to be integrated into an explanogram.


Integrate timestamped sound and/or video into explanogram. It would be useful to allow users to hear (and perhaps see via streaming video) what was said during the development of the written text. Investigating techniques for synchronizing and indexing into sound/video data to allow selective replay of sections of sound associated with areas of the animated text will be the ultimate objective of this area of the project.

Assess alternative methods for presenting the animated data. Flash animations are currently used, but other alternatives exist. What are the benefits and drawbacks of different approaches?

One can identify four major subtasks in this project:

  1. Understanding and capturing the communication between the pen and the computer.

  2. Recording sound, synchronizing it with the penstrokes and upload it to
    the database.

  3. Presentation of the sound and animated penstrokes.

  4. Migrate the system to use a PDA as recording device.

Advisor: Mattias Wiggberg, Arnold Pears

Title: Peer-to-Peer networking. Testbed port and benchmarking

Suitable for: 5-6 DV/MN - students


Peer-to-Peer and Overlay Networks are currently a very hot research topic in both academia and industry due to their promise of a new generation of decentralized and scalable applications. These applications do need some careful design and evaluation however and this is the focus of this project. Using one of the current state-of-the-art academic Peer-to-Peer Networks called "Pasty" we have already implemented a search system which takes advantage of the excellent routing properties of the Pastry network in a simulated environment.


The goal of this project is twofold: 1. To port the application to the PlanetLab testbed and 2. to benchmark the ported version of the application against the original simulated version. The PlanetLab testbed is a global network of academic and industry research groups which host the nodes of the network (currently in the order of 120 nodes) which Uppsala University is a part of. The project should compile a list of metrics (there are already some suggested metrics available to use) which can then be used to benchmark the PlanetLab version of the search application with the simulated version. There is also the opportunity to assist in the creation of a complexity model of the search application. The combination of these two parts of the project will result in a deepened understanding of how the relationship between the simulated environment and an actual real-world implementation. In addition, there is valueable experience to be gained with hands-on experience with both the Pastry Peer-to-Peer Network and the PlanetLab global testbed.

Advisor: Henrik Olsson, Richard Gold, Arnold Pears

Title:Ad hoc (APE) measurements

Suitable for: 5 - students

Construct new APE-scenarios and measure the effeciency of the three protocols in these new scenarios: AODV, OLSR and LUNAR.



Design a new ad hoc networking scenario. Write the scripts for the scenario and the traffic generation. Run the experiments with 5++ nodes and collect and analyze the results.

Redo the experiments at the demonstration day with as many students as possible.

Advisor: Henrik Lundgren, Erik Nordström

Title: WLAN Authentication server for students at Uppsala University

Suitable for: 3-4 IT3 - students


In Building 1 we have been running 802.11b services for students during the last two years. There has been an interest from the university and from the students to scale the infrastructure to eventually cover the whole university. However, the main scaling problem with this solution are the authentication and address (link and IP) handling. The access network is vulnerable from outsiders and from malicious users inside the network.

Currently an authentication server is used for Upunet-S that allows students to log into the university intranet and to get external access.


Design a prototype system that handles student login via Upunet-S authentication server without dealing with MAC-addresses and that provides secure connections.

Advisor: Henrik Lundgren, David Lundberg  (requires an OK from the university)

Title: Security Proxy for Limited Devices

Suitable for: 4 students

Keywords: Security, Proxy, Bluetooth

Ad-hoc distributed systems consist of a variety of devices that use one another’s functionality without relying on central services. These systems gain significance as more and more devices get equipped with computing power and a wireless communication interface allowing them to interact wherever and whenever they meet.

Ad-hoc distributed systems introduce new security challenges. The problem we address in this project is the integration of devices with limited resources into an existing framework by assigning them to proxy devices. Proxy devices are more powerful devices that transparently represent limited devices towards the environment and take care about access control and service discovery.


We implement two approaches that we will compare at the end of the project. One approach uses the security functions of Bluetooth to communicate between the limited device and its proxy device, in the other approach we will dynamically negotiate security parameters that shall be used.

Advisor: Christian Rohner and Oskar Grenholm

Title: Energy saving by using play-out buffers on thin clients.

Suitable for: 3-4 IT3 - students


Wireless 802.11b LAN-cards can receive up to 7 Mbit/s effective data. However, a card consumes quite a lot of battery capacity while in receiving mode. Assume that you want to listen to MP3 music, streamed with 128kbit/s over the wireless LAN. Streaming with 128 kbit/s means that the receiver will be constantly active. Assume instead that the thin client has a playout buffer that can receive music in bursts with the rate of 7 Mbit/s and in between bursts the client turn off the LAN card in order to save battery.


Design a system on a Laptop/Ipaq that can receive music in bursts and in between turns off the card. Optimize the playout buffer size and burst size so that the listening time is maximized. Consider both changing the server to send bursts as well as using a proxy on the network to collect traffic from an unmodified server and subsequently send bursts to the client.

Advisor: Christian Rohner

Title: Vertical handover between Bluetooth - GPRS

Suitable for: 4-5 - students


Today, mobility is important. Travelling and movement is no longer an excuse for breaking the connection to the Internet. To move freely
between different networks maintaining uninterupted connectivity is therefore an important issue.

Different nets may use different technologies for access, LAN, WaveLAN, Bluetooth, GPRS etc. Consequently, a future system should also have
functions for switching between technologies without a broken connection as result.


Create a system that automatically performs a Vertical Handover between GPRS and a Bluetooth. A vertical handover is a seamless, or in theory seamless, switch between two network technologies, maintaining the same connection.

Preferably the system should run on an handheld PDA (IPAQ). Initially it might be necessary to use a laptop as a platform.

Advisor: Mattias Wiggberg¨

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