AG Technische Informatik

Technische Informatik - Network Organization and Protocols (2,3,N)

This seminar is a block seminar, i.e. at the end of the semester, there will be two days when all talks are given in a block. During the semester, there will be deadlines for status reports, but no meetings of the complete seminar group.

Students participating will give a talk and write a report (7 pages as a general rule but each advisor may specify his own requirements). Besides that, they will review one or two reports written by other students and prepare questions to be asked after the corresponding talk. This is to stimulate discussions after the talks and make the seminar more worthwhile.






Stephan Schröder


Institute of Computer Science

Freie Universität Berlin




SS 10






Takustraße 9

K 60



  • Vorbesprechung: Montag, 2.2.2009, 16:00 Uhr (s.t.)

  • Blockseminar: to be announced



Vordiplom or B.Sc., basic knowlegde in telematics

KVV page


  • 2.2.2009:

    • Organizational Meeting - 16:00 Uhr (s.t.), ZIB Takustraße 7, SR 2006

    • Please read the literature linked below.

  • 4.2.2008:

    • Send a list with your five prefered topics in the order of declining preference to seminar-agtech[at]

  • 6.2.2009:

    • You will receive your topic via email.

  • 8-13.3.2009:

    • Meet your advisor to discuss content and structure of your report.

    • Hand in the outline of your report to get feedback.

    • Optional chance to hand in the first version of your report to get even more feedback.

  • starting 30.3.2009:

    • Meet your adviser to receive feedback.

  • 16.4.2009:

    • Introduction to scientific writing - 12-14o'clock (c.t.), ZIB Takustraße, SR 2006

    • Attendance is mandatory!

    • Chance for latecomers to participate in the course and select a topic.

  • 11.5.2009:

    • Your report must be handed in to your advisor and seminar-agtech[at] (see below for formatting instructions).

  • 12.5.2009:

    • You will receive three paper to review them.

  • 1.6.2009:

    • Your reviews must be handed in to your advisor and seminar-agtech[at] (see below for a review form).

  • 2.6.2009:

    • You will get the reviews for your paper.

  • 21.6.2009:

    • Hand in your final report and your slides to your advisor and seminar-agtech[at]

  • to be announced (10.7.2009)

    • The seminar will take place at 14-17o'clock (s.t.) in (probably) SR53. Attendance is mandatory. The talks will be given according to this schedule:

Attention: Students have to meet all deadlines listed in the timetable. Otherwise, she/he will lose the right to take part in the final presentation.


Advisor: Bastian Blywis (Seite)

A Study about Routing Protocol Implementations
Many routing protocols have been proposed in the last decade. Though there usually are implementations for simulation environments, few exist for real operating systems. It is your task to summarize which routing protocols exist, to distinguish particular groups, and to list the existing implementations. Thus, for your report various publications have to be read and the important parts extracted. The following questions have to be answered: Which protocols and groups of protocols exist? Which implementations exist for each of the protocols (e.g. AODV-UU and AODV-UIUC are implemenations of AODV)? Give the ratio between simulation environment and operating system implementations. The gathered data has to be evaluated graphically and summarized accordingly. 
Assigned to: Sebastian Hofmann

A Function Set for Routing Protocol Implementation
To implement routing protocol logic, various functions have to be provided by the operating system or be custom developed. Simple proactive protcols, like OLSR, need routing tables and have to do a periodic neighbor discovery; the gathered information is then advertised to the nodes in the network. It is your task to summarize which functions/features are required to implement most routing protocols. Thus, the reading of various RFCs and publications is required. The relevant parts have to be extracted and summarized in your report. The following questions have to be answered: Which general function/feature set is necessary to implement any routing protocol? Are there distinct groups of features? Which protocols need which functions? Is there some relation between particular groups of routing protocols and particular required features? The gathered data has to be evaluated graphically and summarized accordingly. 
Assigned to: Sebastian Rudniki

Advisor: Norman Dziengel (Seite)

Survey of Data Quality Rating Systems in Wireless Sensor Networks
Wireless Sensor Networks need to rate the quality of collected data within the network. Several approaches of rating data quality in wireless sensor networks have been evaluated in science so far. You have to compare these rating systems. The approaches do rate the quality of data in simple stream of data, in cluster based data or in event based data. Find relevant related work representing the main ideas in this context. Classify the given papers (and papers found by online research) and due to these information give an overview of the state of the art in the context of data quality rating system in Wireless Sensor Networks. Finally evaluate the rating systems respectively the main ideas. 
Assigned to: none

Advisor: Felix Juraschek (Seite)

Simulation vs. Testbed
Simulation environments are a powerful tool to do large scale experiments. Implementations can be done focused on a particular topic without regard to an operating system. As simulators use models that abstract from the reality, experiments can result in measured data that have to be interpreted appropriately. Testbeds on the other hand have scaling problems but use real hardware and real media. It is your task to discuss the differences of simulation environments and testbeds. You have to research how the usage of these two tools has changed over time by reviewing conference papers. 
Assigned to: none

Challenges of experimenting in wireless testbeds
Most research on wireless network is done using simulation environments. These simulators have a limited accuracy because they rely on abstract models. Therefore, wireless testbeds with real hardware gained more attention in the process of performing experiments in an environment as close as possible to real world scenarios. With testbeds, new challenges arise, such as the task of network management and experiment execution in regard of node access, experiment execution and evaluation. The assignment consists of investigating current testbed setups with the focus on the provided experiment framework and how they solve stated challenges in network experimenting. 
Assigned to: none

Advisor: Qasim Mushtaq (Seite)

Comparison of different Link Quality Metrics for Ad hoc Communication
In order to improve the performance of ad hoc communication, different link metrics are used. For example some of the link metrics used are average throughput, delay, signal quality etc. Using each of them is useful in different situations depending to the application requirement. However, calculating the link metrics requires system and network resources. Therefore, a comparison would be helpful in evaluating the advantages and disadvantages of using each link metric under different situations. 
Assigned to: none

Overview of the IP stack in sensor networks
Due to the scare resources in a sensor node, the IP stack is limited. The overview of this IP stack would be helpful in understanding the communication with a sensor node. 
Assigned to: none

Approaches to on-the-fly programming for Sensor Nodes
The sensors nodes have to be programmed before their use. However, there are some techniques that can help to program the sensor node on-the-fly. This is very convenient and helpful, especially when programming a large number of nodes. 
Assigned to: none

Advisor: Pardeep Kumar (Seite)

A Real-time MAC Protocol for Wireless Sensor Networks
In general, the fundamental task of any MAC protocol is to efficiently regulate the access of nodes to a shared medium. However, in the case of resource limited WSN, the MAC protocol has to deal with some additional concerns. The major concerns are energy efficiency and higher latency. Most of the research related to WSN MAC protocols is targeted for the one major objective, the energy efficiency. The timeliness is either dealt as a minor objective or simply ignored. For many applications, such as surveillance, security, environment monitoring, health care, home automation, flood, fire, and seismic detection, the provision of timeliness is as important, as the energy efficiency. In this research, we aim to design a novel WSN MAC protocol, which could efficiently address timeliness challenges, but also provide reasonable trade-offs between timeliness and other vital factors, such as energy efficiency. 
Assigned to: none

IEEE 802.15.4 for Real-time, Bandwidth, and Energy Efficient Medical Applications
The increase in world population, diseases, and natural and non-natural incidents, and the inadequate number of doctors available around highlights the need of an automatic system. Such WSN-based system could efficiently but timely alert medical staff for any mishap regardless to the personal's physical location. It can also be used to store patient records for future research and automatic medication purposes. In this topic, we will discuss the suitability of an emerging IEEE 802.15.4 protocol in the medical field, especially timeliness, energy, and bandwidth related features provided by its MAC layer. Research has shown that the protocol carries many limitations, especially for time critical scenarios and needs definite enhancements before it could be applied to the medical field. We will explore those limitations and propose an efficient solution to overcome those limitations. 
Assigned to: none

Advisor: Heiko Will/Thomas Hillebrandt (Seite)

Energiesparen in Sensornetzen. Vergleich und Analyse verschiedener Verfahren.
Die Minimierung des Energieverbrauchs ist eines der zentralen Forschungsgebiete im Themenkomplex Drahtlose Sensornetzwerke. Energie lässt sich auf allen Ebenen der Entwicklung einsparen - sowohl beim Hardware- als auch beim Softwaredesign. Ziel dieses Seminarthemas soll es sein sich einen Überblick über die Einsparmöglichkeiten auf der Ebene des Funks zu geben. Es sollen sowohl die wesentlichen Taktiken zur Energieeinsparung aktueller Routing- als auch Mac-Strategien untersucht und dargestellt werden. Die herausgearbeiteten Punkte sind ausführlich zu diskutieren und hinsichtlich ihrer Konsequenzen zu anderen Kriterien wie Latenz und Durchsatz zu betrachten. Hierzu ist die Entwicklung einheitlicher und sinnvoller Vergleichskriterien notwendig. 
Assigned to: Joschy Vöhringer

Datensicherheit und Authentizität in Sensornetzwerken
Sensornetze setzen sich zunehmend im praktischen Einsatz durch und werden mittlerweile zur Bauwerksüberwachung bis zum Metering eingesetzt. Ähnlich wie beim Siegeszug des Internets wurde sich bei vielen Umsetzungen um Datensicherheit keine Gedanken gemacht und es ist nur eine Frage der Verbreitung von Sensornetzwerken bis erste Hacks auftauchen werden. Geben sie einen Überblick über Datensicherheitskonzepte auf der Funkebene die speziell auf die Anforderungen von Sensornetzen (schwache Leistung, geringer Overhead, kleine Paketgröße) zugeschnitten sind. Was sind die besonderen Probleme und wie werden sie gelöst? 
Assigned to: Gerrit Gruben

Memory Management in Realtime-Systemen
Neben dem Scheduling ist die Güte des Memory Managements eine der wesentlichen Kenngrößen bei der Beurteilung von Betriebssystemkernen. Overhead und Fragmentierungsvermeidung/--aufhebung spielen die Hauptrollen in klassischen Systemen. Für RT-Systeme kommt eine genaue Vorhersagbarkeit der verwendeten Rechenzeit dazu. Verschaffen Sie sich einen Überblick über aktuell in der Forschung diskutierte Memory Management Strategien und Vergleichen sie diese. Stellen sie Anschließend mindestens eine Strategie für RT-Systeme vor und diskutieren sie die Unterschiede. 
Assigned to: Al-dabab Ali

Wireless Sensor Nodes werden in den unterschiedlichsten Szenarien eingesetzt. Trotzdem werden meist Standardfunktionen wie Scheduling, Nachrichtenübermittlung über Funk und Routing, Logging, Zugriff auf Speicherkarten etc. benötigt, deren Neuentwicklung viel Zeit in Anspruch nehmen würden. Deshalb gibt es auf Mikrokontroller zugeschnittene Betriebssyteme wie TinyOS (, Contiki (, FreeRTOS ( oder TNKernel (, die derartige Funktionalität zur Verfügung stellen. Vergleichen Sie mindestens drei dieser Systeme mit Blick auf Ressourcenverbrauch, Hardwareabstraktion, Scheduling, Programmierschnittstelle (API) und Funktionsumfang." 
Assigned to: Sebastian Lück

Geobasiertes-Routing in Sensornetzwerken
Sensornetzwerke setzen heutzutage eine Vielzahl an Routingprotokollen ein. Kenngrößen sind meistens Latenzzeiten, Overhead und Energieeffizienz. Meistens kommen Sourcerouting oder Distanzvektorrouting zum Einsatz. Ein in der Praxis wenig verbreiteter Ansatz sind Geobasierte-Routingverfahren, bei denen die geographische Position der einzelnen Knoten die Hauptrolle bei der Routenwahl spielt. Führen sie in das Gebiet der Geobasierten-Routingverfahren ein und geben sie einen Überblick über die verschiedenen Ansätze und Lösungen. Arbeiten sie besonders die Probleme heraus die es, im Gegensatz zum konventionellen Routing, beim Geobasierten- Routing zu lösen gilt. 
Assigned to: none

Advisor: Georg Wittenburg (Seite)

Embedded Programming Beyond C
The C programming language is one of the most widely used tools for software development in the area of embedded systems. While limitations of the language are well known, there are few high-profile contenders for the throne of de-facto standard programming language. However, in the area of wireless sensor networks, some new concepts are being explored that may well be worth a second look. The goal of this work is to point out deficiencies of the C programming language in the area of wireless sensor networks and to critically survey alternatives proposed by the research community. 
Assigned to: Uwe Kuehn

Current Approaches to Service Placement in Ad hoc Networks
The goal of service placement is to select which node in a network is most suitable for hosting a service that responds to queries from other nodes. Optimally placing services reduces network traffic and improves connectivity between clients and servers. Practical approaches to service placement commonly employ heuristics based on information gathered from nodes in the neighborhood of the current host. Some heuristics are tailored to the specific application, e.g. coverage, topology or group mobility, and are thus not applicable to general-purpose service placement. The goal of this project is to summarize recent approaches to service placement in MANETs, and to evaluate in detail their strengths and weaknesses. 
Assigned to: none

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