Analys och design för strömmande media i DySCAS

Sammanfattning

This master thesis is a part of the DySCAS project at ENEA. The purpose of this thesis

project is to add support for streaming media and USB support to the DySCAS demonstrator

platform.

To achieve this, some of the widely used middlewares available today were studied. The one

that proved to be of most interest is CORBA. Although CORBA’s solution to streaming

media couldn’t be used due to their use of object programming, the CORBA solution did

provide some interesting thoughts regarding how the USB devices should be handled, in this

case their ”resource inspector” and ”trading service”.

Ethernet was the chosen network to support streaming media. To allow easy handling of

stream there was a need to build a specific protocol. To achieve this, a number of the

protocols used today were studied. The final solution is much influenced by RTP and is sent

on top of UDP.

Extensive studies of USB were made, in the early stages of the master thesis much effort was

made to understand the concept of USB and how drivers were built. Due to the complexity of

USB, building drivers were not an option.

The need for host control stack and drivers led to that OSE had to be discarded and be

replaced by a slimmed version of Linux. This led to that the DySCAS middleware that was

heavily connected to features available in OSE Epsilon had to be migrated to Linux. To

achieve this, the middleware was ”lifted” and all the system calls were mapped to an

equivalent call or function located in an instantiation layer.