Telecommunications Lab
(Lehrstuhl für Nachrichtentechnik)
Saarland University, NTF I - 6.2 Computer Science
Campus C6 3, Floor 10
P.O. Box 151150
66041 Saarbrücken

SS 2007

Main Seminar "Quality of Service in Local Area Networks"


Digital content distributed today in home networks represents a mixture of multimedia and non-multimedia data (e.g. IPTV, VoIP, mp3 download, gaming, browsing). As all applications have different network resource requirements, there is a problem of delivering all the services with certain guaranteed quality (e.g. ftp download may disturb a VoIP application). Quality of Service (QoS) refers to network techniques aiming at improving the user experience of delivering predictable results for some applications (e.g. prioritization of video streaming over file transfer). Network techniques within the scope of QoS include a broad collection of different mechanisms, some of which will be covered within the course of this seminar. The proposed topics include (but not limited to) the following:

  • Application layer methods
    • Scalable audio video coding, adaptive MPEG-4 video streaming, transcoding, transrating, content adaptation.
  • Prioritized/parameterized media access
    • Wireless standards 802.11 vs. 802.11e, WMM - Wireless Multimedia support in Wi-Fi networks.
  • Differentiated forwarding/queuing
    • IEEE 802.1p, WMM, DSCP marking, QoS scheduling algorithms and queue management.
  • Error correction, packet loss control
    • Retransmission schemes (ARQ), Forward Error Correction (FEC) and Hybrid Error Correction (HEC) mechanisms.
  • Transport layer
    • Transport protocols for multimedia streaming (UDP, RTP/RTCP).
  • QoS Management
    • UPnP-QoS, policy-based QoS, Data-Centric QoS vs. User-Centric QoS, resource reservation and management.
  • Standardized approaches for QoS
    • Overview of the available QoS standards from IETF, IEEE, UPnP, CableHome.

Overall organization

The seminar topics will be presented and discussed on the introductory lecture and distributed among the students considering the students’ preferences. Each student will have a supervisor to discuss the work throughout the course of the seminar.

For each topic one student:

  • studies one of the seminar’s subjects
  • writes a report on the studied subject
  • makes an oral presentation

The Seminar will be executed as a block seminar with a set of presentations carried out in the end of the course.


The organizational flow of the seminar is the following:

Date   Time   Place   Event
until 19.04.07       link   On-line registration
25.04.07.   16:00-18:00   C6 3, 9.08   Introductory lecture. Distribution of topics.
25.04.07 - 09.05.07           Reading and understanding the background literature. Discussing the plan of your work with the supervisor.
09.05.07       e-mail   Informal submission of the Table of Contents for the report.
09.05.07 - 06.06.07           Extensive work on the subject. Writing the report. Discussions with the supervisor.
06.06.07       e-mail   Informal submission of the first draft of the report.
06.06.07 - 20.06.07           Further work on the report. Preparing slides for the presentation. Discussions with the supervisor.
20.06.07       e-mail   Informal submission of the first draft of the presentation.
20.06.07 - 04.07.07           Finalizing the report and presentation. Discussions with the supervisor.
04.07.07       e-mail   Final submission of the seminar report and presentation.
10.07.07       16:15-20:00   C6 3, 9.05   Seminar presentations.
11.07.07       18:00-20:00   C6 3, 9.05   Seminar presentations.

Agenda for Seminar Presentations

July 10, 16:15 - 20:00

16:15 Basic QoS mechanisms and techniques

16:45 Prioritized media access in WLANs (EDCA)

17:15 Parameterized media access in WLANs (HCCA)

17:45 Admission control and resource reservation in WLANs

18:15 Break

18:30 Enhancing QoS through RTP

19:00 Adaptive video streaming techniques

19:30 Scalable audio/video coding


July 11,  18:00 -  20:00

18:00 Hybrid Error Correction

18:30 Policy-based QoS

19:00 UPnP QoS Architecture

19:30 Final Discussions


Kick-off meeting, Introduction slides

Contact Person: