Information Technology Reference
In-Depth Information
described
by
delimited
by
Archival
Information
Package
Package
Description
Packaging
Information
derived
from
identifies
Preservation
Description
Information
further described by
Content
Information
Fig. 3.5
Information package contents
It may perhaps have been noticed that the various additional concepts we have
identified are called “Information”. In most cases these will be digitally encoded.
This leads us to a fundamentally important point.
3.3 Recursion - A Pervasive Concept
Those with a mathematical background will recognise some of this
as a type of recursion. It comes up time and again in preservation.
By this we mean that ideas which appear at one level of granular-
ity re-appear when we take a finer grained view, within the detailed
breakdown of those or other ideas. As is well known in mathemat-
ics, it is important to understand where the recursion ends otherwise
it becomes impossible to produce practical results. For example the
factorial function is defined as n!
n
∗
((n-1)!) i.e. 6!
6
∗
(5!)
=
=
=
6
∗
5
∗
(4!)
=
...
This stops when we get to 0! because we define 0! as
equal to 1.
It is worth making some remarks about this concept here.
Representation Information (RepInfo for short) - remember it is
Representation Information rather than Representation Data - is
encoded as data (which could be called representation data but in
fact OAIS does not use that terminology) which itself needs its own
Representation Information. The recursion stops at the Knowledge
Base of the Designated Community.
