Military Communications and Information Technology: A Trusted ...

482 Military Communications and Information Technology...
the data preparation process can be long-term. Each to each method will be used
just this one time only.
First iteration
During operation of the system, achieved connection are registered. For
the next validity period, only those relations that have been registered are established.
Additionally, one should prepare adequate number of spare data sets. Determining
the adequate number is crucial to the success of the method. If the number of spare
data sets is too small, the algorithm will fail and the data protection system will be
unable to perform their tasks. Too large number of spare data sets has no meaning
for the speed of progress, but it prolongs the time of data generation.
Next iteration
If it turns out that the device needs to realize the connection for which
the key has not been prepared, the data loaded into the device will be replaced
with spare data. One should then re-addressed the device and from this moment
the device is identified by a number of spare data set. Information about the change
of the number must be sent out to other devices. Set of relations is updated by
adding the missing relation.
Evaluation criterion
If in a given iteration, all spare data sets are used, it means the negative result
of the algorithm. If in subsequent iterations the number of used spare data sets
is similar, it means that the method is not effective. If the number of used spare
data sets becomes smaller and smaller, it means the positive result of the method.
Probably the number of used spare data never reaches zero, but it is obvious, because
unexpected situations occur always.
VIII. Summary
The proposed adaptive method of cryptographic relations planning combines
advantages of two methods discussed earlier: each to each and according
to needs. The first planning is realized with using each to each method. In subsequent
iterations the set of relations is updated i.e. unnecessary relations are
omitted and necessary ones are included. As the result, the final set of relations
is established, which is realization of “according to needs” conception. The adaptive
method enables to avoid main difficulties connected with previous methods
i.e. manual planning of relations and/or too long time of key generation for all
possible connections.