FIGURE 15 sets out the elements that are the building
blocks of the reconstitution plan 1270. The reconstitution plan 1270 is a compressed list
of the steps required to reconstitute original data files 0220 from the dispersed composite
files 0250 and the index file 0260. The process of reconstituting data 0160 is a precise
and exact step-by-step reversal of the actions taken during the fragmentation run 1740.
For example, some action codes are associated with the opening or closing of files.
Where a code represents opening a file for processing in fragmentation 1740, that code
represents closing the same file and finishing processing of that file in reconstitution
0160. The same reversing effect applies to all actions. One consequence is that files
must be fully identified both when they are opened and when they are closed.
The reconstitution plan 1270 comprises one byte
action codes followed immediately by a trailer appropriate to that action code. In
the plan 1270, action codes and trailers are interspersed as one continuous byte
stream. There are 12 action codes; their numbering is historical accident deriving
from creation of the first prototype. The one essential feature is that the numbers
must be under 256 so that each code may be expressed in one byte. The discussion at
this point views the reconstitution plan as a completed entity; FIGURES 18, 19, and
20 deal with how this entity is created.
Each record 1501 within the reconstitution plan
denotes an action code 01. The most basic process in the system and method to privatize
computer data 0110 is to identify a fragment 1620 from within a original data file 0220,
apply disguising techniques to the fragment, and assign it a location in one of a
plurality of fragment heaps 1651. This process is directed by a fragment handling
guide 1640, which is drawn from a random table 0230. A lengthy series of such actions
1501 can be recorded very compactly in only five bytes -- the 01 code in one binary
byte, the two byte address of a starting location for the first in a series of fragment
handling guides 1640, and the two byte address of the last location in that series.
In the process of reconstituting privatized data 3040 this five byte sequence provides
all that is needed to apply in reverse order a series of fragment handling guides 1640
in order to remove disguises from fragments 1620 drawn now in reverse round-robin order
from composite files 0250 and to reconstitute the original data files 0220 in their
vulnerable form.
