+---+
     | F |
     +---+

FAIL-SAFE DATE

A point in time by when a given status must have been
achieved, failing which, a contingency plan must be
executed to save the situation.  Sometimes called a
"drop-dead date".

FACILITY TESTING

See functional test case design.

FAILURE

Deviation of the software from its expected delivery or
service. [Fenton]

FAT

See FILE ALLOCATION TABLE

FAT DATE RANGE

The range is 1980-01-01 thru 2099-12-31.

A FAT directory entry contains 7 bits (range of values
0-127) for year and defines the year field as "year +
1980", so zero is 1980 and the theoretical maximum
value is 1980+127=2107.  In practice, 2099 is the
maximum value.

On Y2k tickover the RTC (and CMOS mirror) actually goes
back to 1900 (because x'32' is not being set to "20" in
a "non-compliant" BIOS.)

DOS sees the 1900, actually "00", and because 1980 is
the DOS "seed" date i.e. equal to zero, displays as
1980-01-01 or 1980-01-04.  To DOS, 1980 equals Zero.

DOS limits the high and low order dates because of
maxima that can be stored in a FAT formatted
directory structure. Nothing to do with hardware.

Other Operating systems have different constraints.

FAULT

A manifestation of an error in software.  A fault, if
encountered may cause a failure. [do178b]

FEASIBLE PATH

A path for which there exists a set of input values and
execution conditions which causes it to be
executed.(BCS)

FEATURE TESTING

See functional test case design.


FIELD EXPANSION

A technique that converts existing data and programs by
lengthening the year field from two-digits to
four-digits.
(IEEE)

FILE ALLOCATION TABLE(FAT)

A directory maintenance scheme where files are
associated to disk space by means of a track table.
Newer methods are FAT32, NTFS and HPFS.

FILTER

The blocking or passing of data based on specified
criteria
(IEEE)

FIXED WINDOW

A technique to determine the century (high-order
digits) of a year when represented by two digits.  The
2-digit year is compared against a hardcoded threshold.
The century designation is limited to a 100-year range
spanning only two centuries.  For example, assume the
threshold is 60, then if the 2-digit year is ò60, the
year is in the 20th century; if the 2-digit year is
<60, the year is in the 21st century. (IBM)

FLASH BIOS

A normally nonvolatile (read only) memory chip
containing a BIOS program which can be refreshed to a
later level by special programming. Flash BIOS upgrades
are normally only available from the manufacturers of
the specific hardware being used.


FUNCTION TESTING

Testing performed to ensure that a business function is
executed correctly.  May cross system boundaries and
typically starts with a business event and continues
along the work flow to the conclusion of the function.
May include the testing of one or more transactions.


FUNCTIONAL SPECIFICATION

The document that describes in detail the
characteristics of the product with regard to its
intended capability. [BS 4778, Part2]

FUNCTIONAL TEST CASE DESIGN

(see BLACK BOX TESTING)

Test case selection that is based on an analysis of the
specification of the component without reference to its
internal workings.(BCS)