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Tech Note #37:  Introduction to the TOAD
TM
 Protocol
©
1998 Bionic Buffalo Corporation; All Rights Reserved.
                  12 June 1998
http://www.tatanka.com
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11 of 13
TOAD standardizes the use of object identifiers and class names by adhering to the convention
that each such identifier or class name is prefixed with an authority indicator. For example,
CORBA uses text strings to name object classes. In TOAD, an object class name based on
CORBA consists of the CORBA authority prefix, followed by the CORBA text string name of
the class.
Now, the examples:
Automobile
Although various standardized networks are used in automobiles, the objects on those
networks usually have proprietary interfaces. This precludes inexpensive aftermarket
addition or replacement of components in the automobile, since each component must
be designed for a few specific models of automobile.
Suppose the automobile’s lights, horn, engine, sound system, and console were
networked, and defined using standard object interfaces.
Adding an alarm to such a vehicle would be easier than without such standardization.
The alarm could discover the console (to provide a user interface, possibly as a window
on a generic display), lights and horn (to flash or sound in case of violation), engine (to
shut down when there is no authorization), and sound system (to provide voice
interfaces or warning messages). Little or no rewiring would be required.
Adding a cellular phone would also be easier. The cellular phone could discover the
radio, for example, to reduce its volume during calls. The existing sound system might
be used for audio communication with the vehicle’s occupant.
These and other components could be added or replaced, regardless of differing
network topologies in the automobile. For instance, one vehicle design might have
separate sound systems for front and rear compartments. A TOAD-compliant manager
node could arbitrate requests for resources among such multiple sound systems, and
the original component need not have anticipated its use in such an environment.
A simple router (possibly in an external PC) would allow connection of the vehicle to
the internet, for remote diagnostics, maintenance, or software upgrades. This function
is enhanced by use of the TOAD protocol, since it allows operations such as outright
replacement (on the network) of an automobile’s components by alternative, remote
software components.
Without an object discovery protocol (such as TOAD), the automobile would have to
contain a broker or directory service at a well-known address to facilitate these
functions. If well-known addresses were used for all components, the broker might not
be necessary, but on-the-fly replacement of components for diagnostic or maintenance
purposes would not be practical.