When two pieces of data with separate information labels (e.g., objects, files, part of a window's contents) are merged or combined, the system automatically adjudicates the combination of the two information labels, determining the single information label that properly represents the merged data. This process of adjudicating two information labels is also called combining the labels or floating one label with the second one. The values assigned to classifications and the internal compartment and marking bit representations assigned to information label words determine how the system will adjudicate information labels.
When the system adjudicates the classifications from two information labels, the resulting classification is always the classification with the greater internal integer value. Since all classifications by definition form a strict hierarchy, specifying integer values for classifications that represent the hierarchy, with the most sensitive classifications having the highest values and the least sensitive classifications having the lowest values, will assure the proper adjudication of classifications.
Considerations for the proper adjudication of words is much more complicated. The system adjudicates information label compartment and marking bits by performing a bitwise logical “or” of the bit strings, as shown in Table 1–2.
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Proper adjudication is assured by defining the bit representation of each information label word such that the desired properties are enforced when the words are combined via logical “or.” Table 1–3 shows a number of different possibilities for the adjudication of the combination of words. In this and following figures, (NULL) is used to indicate the absence of any word.
As mentioned above, there are two basic types of words: normal and inverse. Additionally, words can optionally appear in a hierarchy with other words. To support these different types of words, the encodings allow for a great deal of flexibility in the association of human-readable word names with internal bit patterns. Rather than simply assigning names to bits, the encodings allow word names to be associated with specific bit patterns. These bit patterns can include compartment bits, marking bits, or both. The examples shown in Table 1–3 are expanded below, showing how the internal encodings of the words implement the desired adjudication of normal words, inverse words, words in hierarchies, composite words, and a more complex example.
In each example, the relevant bit values associated with words are shown as 1s and 0s. Irrelevant bit positions are denoted with –s. Each example below shows two labels and their combination, in both human-readable and internal forms. (NULL) is used to indicate a label containing no words. The bits shown in the examples below could be compartment bits, marking bits, or a combination of both. From the standpoint of label adjudication, there is no difference between compartment bits and marking bits.
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