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Chapter 24
Conclusion
In this chapter we will try to summarize some of the basic conclusions about
what real-time networking medium is best stuited for what situation. These
conclusions can never be valid for all situations but they should hold valid for
most and provide some guidlines for the design phase of new projects that
require network connectivity. It must be noted though that the results here are
based on analysis of the underlaying technology and published performance data.
Due to the very limited availability of performance data and especially the low
quality of this performance data (except for RTnet in all cases the environment
of the tests were not given at all or only incomplete - in most cases not even
the hardware used and the network topology were given), a firm statement on
these issues is not posible without appropriate test/benchmarks and are to be
concidered preliminary.
The networking subsystems are categorized into:
• hard real-time networking
• soft real-time (QOS) networking
• non real-time connectivity to the real-time subsystem
These three categorizatioins are focused on latency - although real-time
networking can also be focused on guaranteed bandwidth allocation this is not
concidered here simply because none of the implementations available target
this issue and provide any usable data on this issues - TODO PART2: benchmark/analyze bandwidth properties of available implementations.
24.1
Hard Real-Time Networking
Ordered by the preference we see for actual application is the list of available hard
real-time networking extensions. Networking is generally viewed as a protocol
based communication between at least two nodes therefore strictly speaking
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