Laboratory for Architecture of Communication Networks (bilingual)
This is the home page of the English part of the lecture
"Laboratory for Architecture of Communication Networks (bilingual)". I
will provide material for this course here in addition to Aula
Global.
Objectives
The Laboratory for Architecture of Communication Networks (LARC) is
an optional lecture for the Telecommunication Engineering career /
Informatics Engineer career. It deal with concepts related to the
communication topics described in related lectures on communication
networks in those careers, mainly shown in the lecture Architecture of
Communication Networks. The principle objective of this lab is the
introduction of fundamental concepts of how to program distributed
multimedia system by designing a simple system for audio transmission
in an audio conferencing system.
For the laboratory the Linux operating system is used.
Announcements, Comments, Schedule etc.
No general announcements right now.
Comments on the laboratory:
- The microphone must be connected to "MIC IN" whereas the headphone
has to be connected to "SPK OUT"
- Take care of the background noise in the laboratory: The
combination heating / air conditioning and the directionality of the
microphone can lead to the fact that under some circumstances the
recording results in a very low quality. To counter this, adjust the
volume for recording and playing adequately and move the microphone to
a different place.
- Execute "kmix" to fix the recording and play-out volume to your
previously stored values.
- If you cannot execute the command "man", try to execute the following command on the command line:
unsetenv MANPATH
Program
After the introduction to the lab (RTP/RTCP, audio device,
transmitting audio data using datagrams), which takes approximately 3
sessions, you can choose one out of three different tasks with an
increasing difficulty (which will also lead to a different grade at
the end).
Choice 1
- Realization of a content server for audio-on-demand.
- Optional: Including IPv6 functionality
Choice 2
- Realization of an audio conferencing system, using RTP and RTCP.
- Optional: Including IPv6 functionality
- Optional: Including NTP information into the RTCP code
- Optional: Detection and processing of silence
- Optional: Operation mode "bounce"
Choice 3
- Realization of a video-on-demand system.
- Optional: Including IPv6 functionality
Teachers
Slides for the Theoretical Sessions
Description of the Different Choices
- Introduction to the laboratory (English / Spanish)
- Part 0: The common part for all (English / Spanish)
- Choice 1: Audio-on-demand server (English / Spanish)
- Choice 2: Audio conference system (English / Spanish)
- Choice 3: The objective is to replace the used medium "audio" in
Choice 2 by video to create a video conferencing system. Therefore,
the video API for linux (v4l) shall be used together with a frame
grabber card based on the BT878 chipset.
Additional Bibliography, Links, etc.
RTP and RTCP: RFC3550, which describes
the protocols RTP and RTCP. Furthermore, RFC3551 could be of interest which deals with
the implementation of audio and video conferencing systems using RTP
and a minimal control.
Audio
Communication
Linux programming
