Database Reference
In-Depth Information
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Arrival Rate
Rajwinder Singh - low
Rajwinder Singh - high
Proposed - low
Proposed - high
Figure 7.5 The impact of varying the arrival rates on the response times of the enhanced secure
multiversion concurrency control model and the Rajwinder Singh model per security level.
the Rajwinder Singh model is the same at the low arrival rates. ThisĀ is
because the conflict area is low. As the arrival rate increases, the
enhanced secure multiversion concurrency control model has better
performance than the performance of the Rajwinder Singh model.
This improvement in the performance is due to the reduction of the
denying time of high classification level transactions and improves
their response time.
In FigureĀ 7.5, the response times of the enhanced secure multiver-
sion concurrency control model and the Rajwinder Singh model are
measured by calculating the response times at each classification level
by using various arrival rates.
7.5 Correctness of the Enhanced Secure Multiversion
Concurrency Control Model
The retrieval anomaly problem has a bad effect on the availability of
the multilevel relational database and it leads high transactions to be
aborted many times [96]. So, there is a great need for a secure con-
currency control model that meets the integrity, security, and avail-
ability requirements for the multilevel relational database. The covert
 
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