Civil Engineering Reference
In-Depth Information
unshielded twisted pair (UTP) cabling or shielded twisted pair (STP) cabling) and
last but not least, cost aspects.
In automotive engineering, bus systems are differentiated according to the so-
called Society of Automotive Engineers (SAE) classes:
5.1.1.1
Class A
Bus systems for simple applications with low data rates of up to 10 kbit/s, e.g., sen-
sor data or simple control commands. The main application domains are relatively
simple functions without safety relevance in the body domain. The transmitted mes-
sages are mainly short and event triggered with a low data rate. The application area
is relatively cost sensitive and demands therefore a rather cheap interconnection
technology.
5.1.1.2
Class B
Bus systems for applications with data rates of 10 kbit/s and up to 125 kbit/s (e.g.,
many more complex body functions).
5.1.1.3
Class C
Bus systems for applications, which require real-time behaviour with data rates of
125 kbit/s and up to 1 Mbit/s (engine domain and chassis domain). In these applica-
tions, domains at high data rates with defined low latencies of data transmission are
required.
5.1.1.4
Class D
Bus systems for the data transmission of long data streams with high bandwidth.
These requirements prevail mainly in the area of infotainment and entertainment,
e.g., for the transmission of audio/video streams.
International Organization for Standardization (ISO) differentiates bus systems
only in two steps:
• Low-speed communication (bit rates < 125 kbit/s) and
• High-speed communication (bit rates > 125 kbit/s).
All these classifications are not really satisfying to adequately describe all the rel-
evant requirements. A classification which is mainly focused on bandwidth is not
sufficient to describe the requirements of the different application domains. Due to
the development towards higher bandwidth and towards wireless data transmission,
this traditional classification concept has to be reconsidered anyway.
