Fiber Optics Illustrated Dictionary - Part 39 docx

Fiber
Optics
Illustrated
Dictionary
of
force
in
a
magnetic
field
taken
as
a
group
(symb.
-
B).
When
expressed
in
terms
of
density
per unit
area,
it
is
calledflux
density
(symb.
-

D).
fly-by
n.
Arepresentation of
movement
from
a
point
of
view
above
the
ground,
commonly
used
in
anima-
tions,
especially
video
games
with
flight
simulation.
Fly-by
animations
give
a
wonderful
sense

of
being
inside
the
scene
that
is
imaged.
NASA
has
produced
some
wonderful
fly-by
animations
of
the
surfaces of
other
planets
such
as
Mars.
Satellite
geophysical
data
make
it
possible
to

create
fly-bys
ofEarth's
surface
right
down
to
individual
buildings
and
streets.
Vir-
tual
reality
fly-by
simulations
are
startlingly
real,
with
participants
ducking
moving
images
so
as
not
to
be
hit.

See
virtual
reality.
fly-page
See
banner.
flyback retrace. In a cathode-ray
tube
(CRT),
the
movement
of
the
electron
beam
tracing
the
image
on
the
screen
from
the
end
of
the
trace
to
the
beginning

where
it
starts
over
on
the
next
line.
Flyback
is
usu-
ally
associated
with
a blanking interval
in
which
the
beam
is
turned
off
so
as
not
to
interfere
with
the
im-

age
already
displayed.
There
is
more
than
one
type
of
flyback
on
a
monitor.
The
flyback
associated
with
scanning
each
line
is
similar
to
the
line
feed
and
car-
riage

return
on
a
typewriter,
in
that
the
scan
finishes
at
the
end
of
one
line
and
flies
back
to
the
next
line
down
(or
two
lines
down
in
interlaced screens)
and

the
beginning of
the
subsequent line,
in
a zigzag
(sawtooth)
pattern.
The
other
type
offlyback
is
when
the
full
video
frame
is
finished,
the
beam
is
at
the
bottom
or
last
line
of

the
screen
and
then
flies
back
to
the
top
or
first
line
of
the
screen.
(This
example
assumes
a
typical
CRT
in
which
the
scanning
is
left
to
right
and

top
to
bottom.)
See
blanking,
frame.
flying
erase headA
mechanism
on
prosumer
and
in-
dustriallevel
VCRs
and
camcorders
that
erases
pre-
viously
recorded
video
traces
that
might
otherwise
interfere
with
new

information
being
recorded
on
top
of
the
same
section.
This
head
is
typically
found
on
systems
that
support insert editing. Rainbows
and
other
undesirable
artifacts
are
thus
avoided.
flytrap A
fIrewall
or
other
security

system
that
logs
unauthorized
attempts
at
access
to
provide
informa-
tion
that
can
help
identify
or
apprehend
the
intruder.
flywheel
1.
A
wheel
that
works
with
other
mecha-
nisms
to

smooth
out
and
reduce
inconsistencies
in
the
rotational
speed
of
the
equipment.
2.
A
wheel
that
is
used
with
other
mechanisms,
whose
purpose
is
to
store
kinetic
energy.
Flywheels
are

often
coupled
with
power
generators
to
continue
the
motion
when
the
generator
mechanism
slows
or
is
idle.
flywheel effect In a transmission that experiences
fluctuations,
the
maintenance
ofa
steadier,
more
con-
sistent
level
of
current,
information,

or
oscillation
by
physical
or
logical
means.
Analogous
to
the
function
ofa
flywheel.
FM
1.
fault
management.
2.
See
frequency
modu-
lation.
FM broadcasting
Transmission
through
frequency
modulation
technologies
on
approved

FM
frequen-
cies
with
the
appropriate
FM
broadcasting
license.
In
372
the
United
States,
FM
stations
are
spaced
at
0.2
kHz
intervals,
ranging
from
88.1
to
107.9
kHz.
Low
power

FM
broadcast
signals
are
used
for
mobile
intercoms,
indoor
intercoms,
monitors,
and
cordless
phones.
See
broadcasting,
FM
broadcasting,
frequency
modula-
tion.
FM transmitter In
its
basic
form,
an
FM
transmit-
ting
system

includes a
microphone,
a
circuit,
and
a
frequency
modulating
(FM)
transmitter.
In
more
so-
phisticated
forms,
it
includes
the
various
commerciaV
industrial transmitters costing
thousands
of dollars
for
broadcasting
from
licensed
radio
news
and

en-
tertainment
and
other
FM
communications
stations.
Building
simple
FM
transmitters
in
the
88-
to
108-
MHz
frequency
range
is
a
very
popular hobbyist
in-
troduction
to
electronics.
With
current
technology,

it
is
possible
to
create
very
compact,
working
FM
trans-
mitters
for
under
$30,
to
broadcast
a
few
hundred
feet
or
even
up
to
two
miles
under
good
conditions.
Be-

fore conducting hobbyist experiments with low
power
FM
transmitters,
it
is
important
to
learn
the
various
Federal
Communications
Commission
(FCC)
restrictions
on
broadcasting,
and
to
honor
laws
pro-
tecting
the
safety
and
privacy
of
individuals.

FMAS
1.
Facility Maintenance
and
Administration
System.
2.
Fund
Management
Accounting
System.
FMV
See
Fair
Market
Value.
FNB
See
Fiberoptics
NewsBriefs.
FNC
See
Federal Networking
Council.
FNEWS A
fast
full-screen
news
reader
for

UNIX,
ALPHA-VMS,
and
VAXNMS
systems,
similar
to
NEWSRDR and ANU-NEWS.
News
articles
for
groups
are
cached
and
dynamically
loaded.
Version
2.0,
released
in
1995,
included
access
security
for
newsgroups
and
removed
the

limits
on
the
size
and
number
of
newsgroups
that
could
be
loaded
FNEWS
is
a commercial shareware
product.
FnorbA
CORBA
2.0
Object
Request
Broker
(ORB)
written
in
Python
and
a
tiny
bit ofC

by
the
Hector
Project participants
at
the
CRC
for
Distributed
Sys-
tems
Technology
at
the
University of Queensland,
Australia.
Fnorb
supports
CORBA
datatypes
and
full
implementation ofIIOP.
It
is
freely
distributable
for
noncommercial
use.

See
CORBA,
ORB.
FNR
1.
Faculty
Network
Resources.
2.
fixed
network
reconfiguration.
Configuration
of
an
existing
network
with static transmission lines
to
support upgraded
services
or
a wider variety ofservices,
often
used
as
an
interim
solution
instead

of
completely replacing
a
network.
FNS
Fiber Network System/Service.
FO-2
A
committee
of
the
Telecommunications
Indus-
try
Association
(TIA)
developing physical-layer test
procedures
and
system
design
guidelines
and
speci-
fications
for
distributors
and
users
of

fiber
optic
com-
munications
technologies.
Since
2000,
plenary
meet-
ings
have
been
held jointly
with
FO-6,
a
TIA
com-
mittee
on
Fiber
Optics.
FOA
1.
fiber
optic
amplifier.
2.
See
Fiber

Optic
As-
sociation,
Inc.
3.
First
Office
Application.
Testing
of
systems
within
an
office
application
once
in-house
testing
is
complete
or
nearly
complete.
Most
of
the
© 2003 by CRC Press LLC
problems
in
the

system
have
been
worked
out
and
what
is
now
sought
is
relevance
and
feedback
from
a
real-world
installation.
In
software
development,
it
is
known
as
beta
testing.
FOe
Firm
Order

Confirmation.
A
product
or
service
agreement
confirmation
document.
foam
dielectric cable A
cable
assembly
that
utilizes
foam
as
a
nonconducting
medium
around
the
con-
ducting
medium
to
reduce
noise
and
increase
trans-

mission
speed.
Foam
dielectric
cables
are
sometimes
substituted
for
air
dielectric.
They
don't
quite
meet
the
performance
characteristics of
the
best
air
dielec-
tric
cables,
but
they
have
advantages
such
as

good
moisture-resistant
properties
and
no
requirement
to
pressurize
the
cable
housing.
See
air
dielectric
cable.
focal
length
(symb.
- f)
In
a
viewing
or
recording
mechanism,
the
distance
from
the
focal

point
on
the
surface
being
viewed
or
recorded
to
the
center
of a
lens
or
surface
ofa
mirror,
as
on
a
camera.
focus
n.
1.
In
an
optical
viewing
or
recording

mecha-
nism,
the
point
at
which
rays
diverging
or
converg-
ing
from
a surface intersect
in
the mechanism
(through
a
lens
or
on
a
mirror)
to
produce
a
clear,
un-
blurred
image
of

the
surface.
2.
In
aprojected
image,
the
point
on
the
projection
surface
in
which
the
rays
converge
to
produce
a
clear,
unblurred
image.
3.
In
a
color
cathode-ray
tube
(CRT),

convergence
of
the
electron
beams
on
a
precise
point
on
the
coated
in-
ner
surface
of
the
glass
to
provide
a
clear
image
on
the
front
surface
of
the
tube.

4.
In
human
vision,
the
point
at
which
the
distance
of
the
object
being
viewed,
the
angle
of
the
individual
parts
of
the
eye,
and
the
angle
of
two
eyes

are
correlated
so
that
the
image
appears
clear
and
unblurred.
4.
Center
of
attention
or
activity.
focus
group A
group
organized
to
concentrate
on
or
discuss
a
specific
issue.
FOD
fax-on-demand.

FODB
See
Fiber
Optic
Data
Bus.
FODTE
See
Fiber Optic Data Transmission Ex-
periment.
FOLDOe
Free
Online
Dictionary of
Computing.
FOLDOC
is
a
popular,
searchable
resource
contain-
ing
over
13,000
concise
definitions
related
to
com-

puting
topics.
FOLDOC
was
established
in
1985
and
is
edited
and
copyrighted
(1993)
by
Denis
Howe.
The
information
is
distributed
for
use
under
the
terms
of
the
GNU
Free
Documentation

License.
/>FOLM
See
fiber
optic
lever
microphone.
FOLS
See
Fiber
Optic
LAN
Section.
FOM
See
fiber
optic
modem.
footprint
1.
An
area
or
impression
on
a
surface
com-
prising
a

more
or
less
contiguous
region
of
contact
with
the
bottom
of
some
object
or
signal.
2.
The
desk
space
or
floor
space
taken
up
by
a
piece
of
furniture
or

equipment,
usually
considered
the
area
of
actual
contact,
or
the
area
of
contact
plus
everything
within
its
boundaries,
and
the
small
area
surrounding
it,
which
may
be
taken
up
by

connectors
or
protruding
knobs.
3.
The
terrain
or
surface of
the
Earth
over
which
a
transmission
signal
can
be
received.
A
trans-
mission
footprint
is
alittle
less
defined
than
a
physi-

cal
footprint,
as
a transmission
tends
gradually
to
decrease
in
intensity
(this
may
be
shown
by
contour
lines
on
a
map
or
chart),
and
there
is
often
no
defi-
nite
cutoff

point,
unless
specified
as
signals
below
a
certain
level.
4.
An
audit
trail
or
traces
left
by
a
trans-
action
or
process
which
has
concluded
or
aborted.
5.
The
resource

requirements
ofa
system.
For
example,
the
Amiga
is
said
to
have
asmall
system
footprint
be-
cause
it
can
adroitly
handle
preemptive
multitasking,
sound,
and
simultaneous animated graphics
in
a
Megabyte
of
memory

on
a
25-
or
40-MHz
processor.
forecasting
Predicting
future
events,
usually
based
on
an
analysis
and
evaluation
ofpast
events.
F
ore-
casting
is
needed
in
all
areas
of
telecommunications
to

choose
technologies that
are
powerful
and
eco-
nomical
and
that
won't
be
quickly
outdated.
It
is
also
used
by
system
administrators
to
configure
and
tune
systems
to
handle
predicted
needs
and

traffic
loads.
Businesses
use
forecasting
to
select
local
area
net-
work
topologies
and
workstations,
and
by
managers
to
organize
employee
loads
and
working
schedules.
See
erlang,
queuing
theory,
traffic
management.

Foreign Agent A
service
enabling
nodes
to
register
at
a
remote
location,
providing
a
forwarding
address
to
a
home
network
in
order
for
forwarded
packets
to
be
retransmitted
to
the
remote location. Foreign
agents

are
an
important
aspect
of
Mobile
IP
systems.
Foreign Exchange Service
FX,
FEX,
FXS.
A
ser-
vice
that
connects
a subscriber's
telephone
to
a
re-
mote
exchange
as
though
it
were
a
local

exchange.
Commercial
vendors
provide
avariety of
multiplex-
ing
interface
cards
to
telecommunications
carriers
to
facilitate
provision of subscriber
Foreign
Exchange
Services.
Forrester, JayWright (1918- )A
computer
pioneer
who
investigated
memory
devices
for
computers
in
the
1940s

and
1950s
while
working
on
the
construc-
tion
of
the
Whirlwind
computer
at
the
Massachusetts
Institute of
Technology
(MIT).
Forrester
was
at
the
forefront
of
transition
technology
from
analog
to
digi-

tal
systems
and
invented
core
memory
with
assistance
from
William
N.
Papian
in
1951.
FORTH
1.
Foundation
of
Research
and
Technology-
Hellas.
2.
Fourth
Generation
Language.
An
exten-
sible, high-level programming language typically
used

in
calculators,
robotics,
and
video
game
devices.
FORTRANFonnula
Translation.
A
high-level
com-
puter programming language that
was
commonly
used
in
the
1980s
for
math-oriented
applications,
and
from
which
BASIC
has
derived
many
of

its
syntacti-
cal
characteristics.
It
grew
partly
out
of
conceptual
ideas
and
examples
of
reusable
code
promoted
by
Grace
Hopper,
and
further
from
the
encouragement
of
John
Backus
that a
language

be
developed
that
could
express
and
solve
problems
in
terms
of
math-
ematical
formulae.
With
the
advent
of
other
languages
such
as
BASIC,
C,
C++,
Perl,
and
Java,
the
use

of
FORTRAN
is
declining.
forum Discussion
group,
private
or
public
meeting,
judicial
assembly.
Electronic
forums
are
common
on
the
Internet.
See
USENET.
373
© 2003 by CRC Press LLC
Fiber
Optics
Illustrated
Dictionary
forum,
online
A

network
virtual
environment
for
dis-
cussions. Internet Relay Chat (IRC) channels,
USENET
newsgroups,
discussion
lists,
and
various
meeting
places
on
Web
sites
are
examples
of
global
forums
where
topics
are
ardently
and
enthusiastically
debated.
When

forums
include
celebrities,
they
are
usually
moderated
to
keep
the
questions
and
com-
ments
to
a
manageable
level.
Forum for Responsible and Ethical Email
FREE.
An
organization
for
education
and
assistance
to
in-
dividuals
and

groups
seeking
to
balance
the
need
for
freedom
to
send
email
and
the
need
for
respecting
the
personal
privacy
and
economic
rights
of
email
recipi-
ents.
FREE
sponsors
an
informational

Website,
dis-
cussion
groups,
and
provides up-to-date
news
on
spam-related
issues
in
the
media
and
the
legislature.
l
Forum ofIncident Response and Security
Teams
FIRST.
A
global
coalition
established
in
1990
to
fos-
ter
the

exchange
of
information
and
response
coor-
dination
among
computer
security
teams.
Participants
come
from
a
variety
of
academic,
commercial,
and
governmental
organizations.
Part
of
the
motivation
for
establishing
FIRST
came

from
the
1988
events
associated with
the
spread
of
the
Internet
Worm,
which
made
it
clear
that
economic
damage
and
loss
of
productivity
were
very
real
threats
to
the
global
Internet

and
that
coordinated efforts
to
respond
to
such
incidents
would
be
more
efficient
than
the
hit-
or-miss
response
to
the
spread
of
the
Internet
Worm.
FIRST
fosters
cooperation
among
technology
and

security
experts
and
facilitates
research
and
opera-
tional
improvements
to
support
secured
networking.
See
Computer
Incident
Advisory
Capability,
Com-
puter
Emergency
Response
Team,
WORM,
virus.
l
forward error correction
FEC.
A
means

of
ensur-
ing
a
transmission
in
advance
by
duplicating
infor-
mation
or
otherwise
improving
the
chances
of
its
be-
ing
received
the
first
time.
For
example,
characters
or
groups
of

characters
may
be
sent
two
or
more
times
(called
mode
B
in
amateur
radio
transmissions)
ac-
cording
to
a
predetermined
arrangement.
Repeating
characters,
or
groups
of
characters,
in
data
transmis-

sions
gives
a
receiver
an
opportunity
to
compare
the
groups
and,
if
any
of
the
information
doesn't
match,
request
a
retransmission.
The
basic
idea
is
to
mini-
mize
the
back

-and-forth nature of handshaking
to
speed
a
transmission
while
still
giving
information
that
may
be
used
to
check
the
integrity
of
the
infor-
mation
being
received.
Forward Explicit Congestion Notification
FECN.
In
a
Frame
Relay
network,

a
bit
used
to
notify
an
in-
terface
device
to
initiate
congestion-avoidance
pro-
cedures
in
the
direction
of
the
received
frame.
See
Backward
Explicit
Congestion
Notification.
Forwarding Equivalence Class
FEC.
In
Multipro-

tocol
Label
Switched
(MPLS)
networks,
the
FEC
is
a
networking
categorization
scheme
associated
with
packet-forwarding.
A
specific
FEe
includes
destina-
tion
address
information
and
may
include service
information.
FEe
details are managed within a
374

router's forwarding information base (FIB).
See
Multiprotocol
Label
Switching.
FOS2
See
Fiber
Optics
Sensors
&
Systems.
FOSS
1.
Facilities
Operations
Support
Services.
Ser-
vices
at
the
Stennis
Space
Center.
2.
See
fiber
optics
sensing

system.
3.
Future
of
Space
Science.
FOT
Fiber
Optic
Terminal.
A
connection
point
or
de-
vice
at
which
a
fiber
optic
circuit
connects
to
a
cop-
per
wire
circuit.
FOTS

fiber
optic
transmission
system.
Foucault test A
type
ofoptical
null
test
(a
test
using
the
instrument
itself)
for
determining
the
optical
qual-
ity
ofaspherical
surface
relative
to
the
center
of
cur-
vature

of
the
component
with
a
point
light
source.
See
Dall
test,
Ronchi
test,
star
test.
Foucault,
Jean
Bernard
Leon (1819-1868) A
French
physicist
best
known
for
his
studies
of
the
speed
oflight

and
the
rotation of
the
Earth
through
the
use
of
pendulums,
Leon
Foucault
also
developed
a
gyroscope
(1852)
and
a
mechanical
telegraph.
In
1850
he
was
awareded
the
Copley
Medal
by

the
Royal
Society
of
London
for
his
work
on
the
rela-
tionships
between
heat,
magnetism,
and
mechanical
energy.
He
also
studied
photographic
processes
and
vision.
See
knife-edge
focusing.
Fourier, Jean Baptiste Joseph
(1768-1830)

Fourier,
a
French
mathematician
and
lecturer,
discovered
in
the
early
1800s
that
the
superposition
of
sines
and
cosines
on
time-varying
periodic
functions
could
be
used
to
represent
other
functions.
He

made
practical
use
of
these
techniques
in
the
study
of
heat
conduc-
tion,
work
that
was
developed
further
by
G.
S.
Ohm
in
the
1820s
in
his
mathematical
descriptions
of

con-
duction
in
circuits.
Work
on
linear transformation
mathematics
that
predated
Fourier's
publications
was
carried
out
by
Karl.
F.
Gauss
but
went
unpublished
until
after Fourier's
descriptions.
See
Fourier
trans-
form.
Fourier analysis A

means
of
representing
physical
or
mathematical
data
by
means
ofFourier
series
or
Fourier integrals.
Fourier transform Alinear
mathematical
data
ma-
nipulation
and
problem-solving
tool
widely
used
in
optics,
transmissions
media
(antennas),
and
more.

The
superposition of
sines
and
cosines
on
time-vary-
ing
functions
can
be
used
to
represent
other
functions,
in
other
words,
to
represent
the
data
from
another
point
of
view.
The
result of

such
a
transformation
is
to
decompose
a
waveform
into
subsets
ofdifferent
frequencies,
which
together
sum
up
to
the
original
waveform.
In
this
way,
the
frequency
and
amplitude
can
be
separately

and
more
easily
studied.
A
rudimentary
application ofFourier
series
calcula-
tions
were
used
to
utry nderstand planet orbits
in
Greek
times.
Their
development
was
in
part
ham-
pered
by
the
Greeks' mistaken
assumption
that
the

Earth
was
the
center of
the
universe.
Fourier
transforms
differ
from
wavelet
transforms
in
that
they
are
not
localized
in
space;
however,
they
also
share
many
common
characteristics.
Named
after
J.BJ.

Fourier.
See
discrete
cosine
transform,
wave-
let
transform.
© 2003 by CRC Press LLC
Fourier transform, fast
FFT.
This
optimized
ver-
sion
ofa
Fourier
transform
was
developed
in
1965
by
Tukey
and
Coo
ley.
It
substantially
reduces

the
number
of
computations
needed
to
do
a
transform,
hence
the
name.
FFT
computations
are
used
in
many
types
of
imaging
applications (e.g., filtering a
3D
image
to
display
a
2D
interpretation).
fox

messageA
test
sentence
that
includes
all
the
let-
ters
of
the
English
alphabet,
commonly
used
to
verify
if
all
letters
of
the
English
alphabet
in
a
device
or
coding
system

are
present
and/or
working
correctly.
Familiar
to
most
as
"THE
QUICK
BROWN
FOX
JUMPS
OVER
THE
LAZY
DOG"
(which
may
then
be
repeated
as
all
lowercase,
as
needed).
FPLMTS
See

Future
Public
Land
Mobile
Telecom-
munication
System.
fps
See
frames
per
second.
FPU
See
floating
point
unit.
FRA
See
Fixed
Radio
Access.
fractal A
term
popularized
by
Benoit
Mandelbrot
to
describe

his
geometric
discoveries
and
descriptions
of
structures
that
can
be
described
and
reproduced
as
mathematical formulas and
have
the
character-
istics
of
self-similarity
in
increasingly
fine
degrees
of
detail.
Fractal
concepts
have

since
permeated
almost
every
aspect
of
computing,
especially
computer
image
dis-
play,
compression,
and
reconstruction.
Fractal
geom-
etry
provides
a
means
to
model
surprisingly
complex
and
natural-looking structures
with
simple
math-

ematical
formulas.
See
the
Fractal
Geometry
ofNa-
ture
by
Benoit
Mandelbrot.
Fractal
Image
Format
FIF.
A proprietary
image
compression
format
developed
by
Michael
Barnsley
and
Alan
Sloan,
who
together
founded
Iterated

Sys-
tems,
Inc.
to
exploit
the
technology.
Very
high
rates
of
compression
are
possible.
The
technology
is
asym-
metric
-
it
takes
a
while
to
compress
the
information,
but
it

decompresses
relatively
quickly.
See
fractal
transform.
fractal transform, fractal compression A
resolu-
tion-independent, lossy
image
compression
tech-
nique
providing
a
high
degree
of
perceptual
similar-
ity
with
excellent
compression
results.
Fractal
com-
pression
works
by

storing
image
components
in
terms
of
mathematical
algorithms,
rather
than
as
individual
pixels
ofa
particular
location
and
color.
The
organi-
zation
of
the
image
is
evaluated
for
its
intrinsic
char-

acteristics
of
self-similarity,
and
those
characteristics
are
coded
so
they
can
be
reproduced
by
repetitions
in
increasingly
fine
detail,
up
to
the
resolution
of
the
output
device.
With
their
excellent

image
fidelity
and
high
compres-
sion
ratios,
the
trade-off
in
fractal
compression
is
the
time
it
takes
to
encode
or
decode
and
display
the
de-
compressed
image.
With
faster
processors,

this
is
be-
coming
less
ofa
limitation.
See
lossy
compression;
discrete
cosine
transform;
Fisher,
Yuval;
JPEG;
Man-
delbrot,
Benoit;
wavelet
transform.
fractals, fractal images A
term
borrowed
from
frac-
tal
geometry
to
describe

visual
images
that
have
rec-
ognizable
visual
and
mathematical
characteristics of
self-similar,
repeating
branches
and
curves
resulting
from
the rendering
of
fractal formulas. Colored
fractals
can
be
beautiful,
and
they
adorn
many
cal-
endars,

posters,
and
t-shirts.
Many
familiar
fractal
for-
mulas
have
been
given
names,
such
as
Julia
Set,
Man-
delbrot
Set,
etc.
See
Mandelbrot,
Benoit.
FRAD
See
Frame
Relay
access
device.
fragmentation

1.
State
of
being
broken
up,
separated
into
units
or
groupings,
having
lost
connections
or
cohesiveness,
or
physically
or
logically
separating
over
time.
2.
In
hard
drive
storage,
fragmentation
is

a
gradual
process
of
the
available
or
used
areas
ofa
drive
becoming
smaller
and
more
widely
dispersed.
When
information
is
stored
on
a
hard
disk
or
other
similar
directory-based
system,

files
are
placed
where
there
is
room
on
the
drive
and
sometimes
spread
over
a
number
of
areas
on
the
drive.
When
a
file
is
deleted,
its
directory
entry
is

removed
and
the
space
it
occu-
pied
becomes
free
for
other
files.
However,
over
time
(especially
with
a
lot
of
disk
activity),
the
free
areas
get
smaller
and
farther
apart,

and
files
stored
on
the
drive
need
an
increasing
number
of
sections
and
links
to
keep
track.
This
fragmentation
slows
down
the
sys-
tem.
It
is
sometimes advisable
to
defragment or
"defrag" a

drive
to
optimize
the
tables
and
file
data
locations.
Some
operating
systems
have
built-in
utili-
ties
for
rebuilding
a
drive
or
system.
It
is
important
that
sufficient
memory
and
swap

space
are
available
on
a
system
before
de
fragmenting
a
drive,
and
it
is
highly advisable
to
back
up
the
data
first.
frame
1.
A
bounded
visual
or
logical
unit
or

block
of
related
information,
sometimes
delimited
with
visual
or
binary
flags
or
markers.
A
frame
is
sometimes
a
natural
unit,
as
in
a
cyclic
event
in
which
the
infor-
mation

repeats
in
some
general
sense
(though
the
con-
tent
may
vary),
and
sometimes
it
is
an
arbitrary
unit,
chosen
for
convenience
or
by
convention.
2.
A
physi-
cal
unit,
border,

containment
area,
skeleton
(frame-
work),
or
inclusive
extent.
3.
A
full-screen
perceiv-
able
image
on
a
monitor
or
TV
screen
consisting
of
the
sum
of
all
the
sweeps
of
an

electron
gun
during
a
full
cycle
ofoscillations
across
the
screen.
4.
A
unit
of
information
in
data
networks
such
as
Frame
Re-
lay
systems.
5.
A
contained
group
ofinfonnation
on

an
HTML
layout,
such
as
a
Web
page.
6.
A
housing
or
support
structure
for
components
or
wiring.
See
distribution
frame,
rack.
frame,
data
In
most
networking architectures, a
frame
is
a

group
of
data
bits
ofa
fixed
or
variable
size,
often
in
a specified
format.
It
is
common
for
frames
to
be
organized
into
two
general
types:
those
which
carry
signaling,
addressing,

or
error
detection!
correction information,
and
those
which
carry
the
contents of
the
communication itself (sometimes
called
payload),
although
even
these
are
sometimes
combined.
The
format
and
organization
of
the
frames
are
defined
by

a
data
protocol,
and
there
are
many
general
purpose
and
specialized protocols
in
use,
most not directly compatible with
one
another.
Interprotocol
frame
traffic
can
be
carried
or
tunneled
through
other
protocols
or
can
indirectly

communicate
through
conversion
agents
or
filters.
375
© 2003 by CRC Press LLC
Fiber
Optics
Illustrated
Dictionary
Frames
are
organized
into
larger
units
comprising
a
communication
and
then
may
be
sent
together
to
the
destination,

or
they
may
be
disassembled,
sent
along
different
paths,
and
reassembled
at
the
destination.
Frames
may
also
be
encapsulated,
wrapped
in
an
outer
envelope,
to
carry
them
through
a
system

that
requires
another
format
or
to
tunnel
through
a
sys-
tem
without
having
the
contents
of
the
encapsulated
package
changed
in
any
way.
It
is
then
de-encapsu-
lated
at
the

exit
point
or
at
the
destination.
When
frames
carry
different
types
of
data,
such
as
graphics
in
one
and
sound
in
another,
they
are
some-
times
sent
simultaneously
through
separate

wires
or
data
paths
and
reassociated
at
the
receiving
end,
as
in
videoconferencing.
In
these
situations,
synchroni-
zation
or
alignment
of
information
is
important
and
information
for
achieving
this
may

be
included.
See
Frame
Relay,
Frame
Relay
frame
format,
protocol.
frame, distribution A wiring
connection
physical
supporting
structure.
See
distribution
frame.
frame,
video
In
video
displays
that
cyclically
sweep
the
full
screen
to

create
an
image,
a
frame
is
the
ex-
tent of
the
sweep
that
is
required
to
cover
the
full
screen.
In
the
NTSC
system prevalent
in
North
America,
the
sweep
is

29.97
frames
per
second
and,
on
an
interlaced
screen,
is
further
subdivided
into
two
sets
offields
(all
odd
lines
or
all
even
lines).
The
for-
mats
that
are
common
in

Europe
(pAL,
SECAM)
dis-
play
at
24
or
25
frames
per
second.
It
is
important
to
time
the
frame
presentations
at
a
broadcast
station,
so
that
news
briefs,
commercials,
and

regularly
scheduled
programming
can
be
orga-
nized
into
precise
time
slots.
NTSC
displays
are
generally
525
scanlines, though
not
all
the
bottom
scanlines
may
be
visible
on
the
screen.
European
stan-

dards
are
625
lines.
A
frame
is
an
important
unit
in
video
display
not
only
for
physical
synchronization
of
the
signals,
but
also
because
the
rapid
sequential
presentation ofstill
frames
creates

the
illusion of
movement,
and
the
properties
of
this
illusion
must
be
taken
into
consideration
if
creating
still-frame
ani-
mation
sequences.
See
station
clock.
See
television
signal
for
a
chart
of

common
formats.
frame alignment signal
FAS.
In
frame-based
trans-
missions,
a
sequence
of
bits
intended
to
provide
fram-
ing
alignment
information
for
synchronization
pur-
poses.
In
other
words,
it
provides
the
necessary

in-
formation, usually
at
the head
of
a sequence
of
frames,
for
the
receiver
to
synchronize
itselfwith
the
incoming
signal.
The
signal
may
also
include
status,
control,
and
error-relatedbits. The bits following the
frame
alignment
signal
are

often
allocated
to
more
specific
alignment
or
configuration
tasks
(e.g.,
chan-
nel
setup),
and
thereafter
there
is
usually
information
content.
frame buffer A
storage
area
used
for
preconstruct-
ing
digital
images
in

order
to
facilitate
the
quick
dis-
play
of
those
images, especially
if
they
are
to
be
displayed
one
after
another,
as
in
a
sequence
of
ani-
mation
frames.
The
image
in

the
frame
buffer
is
not
necessarily displayed
all
at
once.
For
example,
in
video
games,
it
is
very
common
to
store
a
wide,
ver-
376
tically
narrow
panoramic
landscape
in
a

frame
buffer
and
to
display
only
aportion
of
the
scene
at
anyone
time.
Then,
as
the
characters
in
the
game
move
along
the
landscape,
the
display
scrolls
smoothly
to
right

or
left,
without display artifacts
such
as
flicker
or
jumping that
may
be
caused
by
disk
reads
or
off-
screen
reconstruction
of
the
image.
Frame
buffers
are
commonly
used
for
high-speed,
high-resolution
ap-

plications such
as
computer animations, arcade
games,
and
video
walls.
See
frame
store.
Frame Check Sequence
FCS.
A
mathematical
al-
gorithm
that
derives
a
value
from
a
transmitted
block
of
information
and
uses
the
value

at
the
receiving
end
of
the
transmission
to
determine
whether
any
trans-
mission
errors
have
occurred.
FCS
is
used
in
bit-oriented
protocols
such
as
SNA
SDLC
to
determine
if
sent

and
received
messages
are
the
same.
For
example,
in
SDLC
the
two-byte
(16-
bit)
FCS
field
includes
a
cyclic
redundancy
check
(CRC)
value
used
to
assess
the
validity of
the
re-

ceived
bits.
frame grabber A
computer
hardware/software
pe-
ripheral device designed
to
capture
and
digitize a
frame,
or
series
of
frames,
from
a
continuous
signal,
usually
from
an
NTSC
source
(a
frame-based
video
signal).
The

signal
generally
comes
from
live
video,
laserdisc,
or prerecorded
tape.
It
is
sometimes
called
a
video
capture
board
or
video
digitizer.
The
faster
a
frame
grabber
can
capture
frames,
the
more

true
to
the
original
signal
a
playback
of
the
grabbed
frames
will
appear.
Generally
speeds
of
about
24
frames
per
second
are
required
for
a
video
animation
to
appear
natural

to
the
viewer.
See
frame
buffer,
sampling.
frame merge
1.
Over
frame-based
media,
a
stream
merge.
2.
In a
Frame
Relay
network,
frame
merge
can
be
used
as
a
way
to
forward

IP
packets
or
por-
tions
of
packets
inside
a
frame,
rather
than
on
an
in-
dividual cell basis,
to
improve
the
scalability of a
network
while
avoiding
problems
with
scaling
vir-
tual
circuits
(VCs).

3.
Frame
merging
is
useful
in
cases
where
data
streams
are
coming
from
more
than
one
source,
but
the
software
can
only
handle
one
in-
put
stream
at
a
time.

In
these
cases,
there
are
utilities
available
to
merge
the
data
streams
in
various
ways,
depending
upon
the
type
of
data
that
is
being
received
and
how
it
is
intended

to
be
processed.
4.
The
phrase
frame
merge
is
sometimes
loosely
used
to
refer
to
convergence
of
data
and
telephony
services
for
com-
panies
that
are
seeking
ways
to
integrate

their
busi-
ness
telephone
services
with
their
data
services
on
the same permanent virtual circuit (VC). Data-tele-
phony
convergence
over
Frame
Relay
is
a
better
way
to
describe
this
process.
frame
mode
In
video
image
capture,

a
mode
that
cap-
tures
a
full
frame
of
scan
lines
more
or
less
simulta-
neously
in
contrast
to
most
desk
scanners,
which
cap-
ture
a
line
or
block
of

the
image
at
a
time.
Full
frame
images
preserve
image
integrity
but
also
take
more
storage
space
than
some
modes.
Most
digital
cameras
are
frame
mode
capture
devices.
See
field

mode.
frame rate, video
The
speed
at
which
a series
of
images
is
presented
or
a
screen
of
visual
information
© 2003 by CRC Press LLC
is
drawn,
usually
expressed
in
seconds.
Due
to
per-
sistence
of
vision

in
human
perception,
individual
still
images
presented
at
about
20
frames
per
second
or
faster
give
the
illusion
of
motion.
At
speeds
of
over
30
frames
per
second,
no
substantial

improvement
in
the
animation
quality
is
perceived
by
most
people.
Motion
picture
film
is
usually
displayed
on
35mm
projectors
at
24
frames
per
second.
Home
8mm
and
Super-8mm
projects
are

somewhat
variable
around
20
to
24
frames
per
second,
since
most
have
dials
to
speed
up
or
slow
down
the
film
transport
rate.
North
America
TV
is
broadcast
at
about

30
frames
per
second.
(In
actual
fact,
due
to
differences
between
black
and
white
and
color technology,
the
rate
is
closer
to
29.97
frames
per
second.)
On
various
Eu-
ropean
systems,

such
as
PAL
and
SECAM,
broadcast
frame
rates
are
24
or
25
frames
per
second.
On
computer
systems,
frame
rates
vary
with
the
soft-
ware
that
is
creating
the
frames

or
with
the
software
playing
the
frames.
Smaller
video
windows
can
be
played
back
faster
than
large
ones,
as
they
take
less
time
to
compose
and
require
less
computing
power

to
display.
Displays
of
256
colors
also
refresh
faster
than
24-bit
displays
(-16.9
million
colors),
although
refresh
will
vary
with
the
system
speed
and
type
of
graphics
card
used.
On

systems
less
well
adapted
to
video,
rates
may
vary
from
20
to
30
frames
per
sec-
ond.
Videoconferencing systems running over analog
phone
lines
may
refresh
only
at
frame
rates
of 5
or
10
times

per
minute,
as
the
voice-grade
lines
and
mo-
dem
create
a
bottleneck.
On
ISDN
and
other
digital
lines
that
run
at
faster
rates,
20
or
more
frames
per
second
may

be
possible,
depending
upon
the
type
of
system
and
the
size
of
the
image
window.
See
drop
frame,
MIDI
time
code,
SMPTE
time
code.
Frame
Relay,
Frame Relay network
Frame
Relay
is

a
networking
connection
option
often
selected
by
smaller
businesses
as
acost-effective
way
to
set
up
a
reasonably
fast
and powerful
wide
area network
(WAN)
or
local
area
network
(LAN)
that
can
connect

with
public
networks.
Frame
Relay
can
be
used
across
Integrated
Services
Digital
Network
(ISDN)
and
a
number
of
other
interfaces
to
interconnect
multiple
virtual
LAN
s
at
lower
rates
than

the
cost
of
leased
lines.
Standardization
efforts
for
the
technology
were
initiated
in
the
early
1980s
and
continued
for
a
num-
ber
of
years.
In
1990
and
1991
vendors
formed

associations
to
fa-
cilitate
development
and
deployment
of
the
technol-
ogy.
Viable commercial implementations began
emerging
in
the
early
1990s.
Frame
Relay
is
a
connection-oriented,
packet
-switch-
ing
protocol
designed
to
provide
virtual

circuits
(VCs)
for
interconnections
within
the
same
Frame
Relay
net-
work.
Virtual
circuits
may
be
permanent
or
switched
(similar
to
Ethernet). Permanent virtual circuits
(PVCs)
are
more
prevalent,
but
switched
virtual
cir-
cuits

(SVCs)
are
of
increasing
interest.
Frame
Relay
evolved
from
and
is
somewhat
simpli-
fied
over
X.25.
For
example,
Frame
Relay
is
con-
cerned
with
packet
delivery without
sequence
and
flow
control,

resulting
in
faster
throughput
and
some-
times
lower
cost
by
trading
off
error
correction
at
the
network
level.
(Error
correction
can
be
implemented
by
intelligent user
terminal
equipment,
depending
upon
needs.)

Frame
Relay
has
been
shown
to
work
in
practical
situations
up
to
almost
50
Mbps.
Frame
Relay
operates
at
the
physical
(PRY)
and
data
link
layers
of
the
Open
Systems

Interconnect
(OSI)
reference
model.
It
is
implemented
as
a
Layer
2
pro-
tocol.
The
physical
interface
can
interconnect
mul-
tiple
remote
networks
through
Frame
Relay
switches.
Frame
Relay
can
transport

a
number
of
encapsulated
~~:!Ss::~::s:::'p::::::::
::i::t:~:e
:::~
.~.
nection
status
of
the
link.
In
a Point-to-Point
(PPP)
system,
Frame
Relay
framing
is
treated
as
a
dedicated
or
switched-bit-synchronous
link.
See
Asynchronous

Transfer
Mode,
cell relay, Data Link
Connection
Identifier,
framing
bits,
and
additional
entries
pref-
aced
by
Frame
Relay.
Frame Relay access channel A
user
access
channel
across
which
Frame
Relay
data
travels.
The
access
channel
specifies
the

physical
layer
interface
speed
of
date
terminal
equipment
(DTE)
and
data
commu-
nications
equipment
(DCE).
An
access
channel
may
be
categorized
as
unchannelized,
channelized,
or
frac-
tional.
When
the
entire

DS-3/TIIEI
is
used
at
speeds
of 45/1.536/1.984
Mbps,
respectively,
as
a single
channel,
it
is
considered
to
be
unchannelized.
When
DS-3/TllEl
lines
have
one
or
more
channels
oper-
ating
at
aggregate
speeds

not
exceeding
those
just
listed
for
unchannelized
transmissions,
they
are
con-
sidered
to
be
channelized,
with
the
channel
as
any
of
Ntime
slots
in
a
given
line.
In
TIIEl,
consecutive

or
nonconsecutive
time
slots
are
grouped
as
Nx56,64
Kbps/Nx64
Kbps
where
N = 1
to
24
or
1
to
30
DSO
time
slots
per
channel,
respectively,
and
are
consid-
ered
fractional.
FrameRelay

access
rate
The
data
transmissions
rate
of
the
Frame
Relay
access
channel.
It
is
the
maximum
rate
at
which
the
user
can
insert
data
into
the
Frame
Relay
network.
Frame Relay access device

FRAD.
Another
name
for
the
switch,
router,
or
other
network
device
that
assembles
and
disassembles
Frame
Relay
frames
as
they
are
transported
through
a
system.
When
data
frames
are
sent

over
a
Frame
Relay
network,
they
are
packaged
with
various
types
of
information,
often
at
the
beginning
and
end
of
the
block of
frames,
and
unpackaged
again,
often
at
the
access

point
to
the
des-
tination
system
to
recover
the
structure
and
contents
of
the
original
communication.
Frame Relaying bearer service
FRBS.
A
service
providing
bidirectional transfer of
service
data
units
(SDUs)
from
one
reference
point

to
another,
retain-
ing
the
order
of
frames.
FRBS
trades
off
some
aspects
of error processing (e.g., acknowledgments) for
speed.
A
local
label
facilitates
device
identification
over
virtual
connections.
Frame Relay cloud A
Frame
Relay
network
that
is

shared among a small number
of
participating
377
© 2003 by CRC Press LLC
Fiber
Optics
Illustrated
Dictionary
subscribers
in
order
to
get
the
benefits
of
the
tech-
nology
at
a lower
cost.
It
is
a suitable option
for
smaller
businesses
that

do
not
have
high
networking
demands
but
would
like
higher
speeds
than
are
avail-
able
through
dialup
modem
connections,
for
example.
The
system
can
handle
a firm's
voice
and
data
com-

munications
needs.
As
data
passes
through
the
cloud,
it
is
handled
by
switches,
depending
upon
how
the
virtual
circuit
has
been
configured
to
accommodate
each
subscriber's
networking
needs.
Frame
Relay

devices
The
common
devices
that
com-
prise
a
Frame
Relay
network
include
computers,
ter-
minals,
and
circuit-related
equipment.
They
generally
fall
into
two
categories,
data
terminal equipment
(DTE)
and
data
circuit-terminating

equipment
(DCE).
The
DTEs
(desktop
computers,
terminals,
routers,
etc.)
are
usually
located
on
the
subscriber's
premises,
while
the
DCEs
(the
various
circuit-connecting
and
-switching
devices)
may
be
locally
installed
or

may
be
managed
by
the
Frame
Relay
service
provider.
Frame
Relay
extensions
A
consortium
of
vendors
seeking
to
enhance
the
basic
capabilities
of
Frame
Relay
in
order
to
meet
the

demands
of
the
commer-
cial
marketplace
extended
the
Frame
Relay
protocol
with
a
Local
Management
Interface
(LMI)
specifi-
cation
in
1990.
Organizations
such
as
CCITT
(now
lTU-
T)
andANSI
developed

versions
of
the
LM!
that
are
now
generally
adopted.
The
LM!
is
a
specification
for
information
exchange
between
devices
that
is
enhanced
with
capabilities
such
as
global
addressing,
multicasting,
and

addi-
tional
status
messages.
The
frame-relay
lmi-type
in-
terface
configuration
command
provides
a
means
to
select
the
type
of
LMI
interface,
and
the
Frame
Re-
lay
keepalive
command
enables
LMI

for
serial
lines.
LMI
statistics
can
be
displayed
with
the
show
frame-
relay
lmi
EXEC
command.
Frame Relay
flow
control
Flow
control,
the
man-
agement
ofmovement offrames
within
and
between
networks,
is

not
explicitly
defined
in
the
Frame
Re-
lay
specification,
and
the
lTV
has
defined
general
concepts
and
standards
for
handling
flow
and
con-
gestion.
In
practice,
congestion
can
be
prevented

in
Frame
Relay
networks
by
establishing
committed
in-
formation
rates
(CIRs)
to
each
user,
denying
the
con-
nection
if
insufficient
bandwidth
is
available,
and
by
discarding
frames
above
the
CIR.

Existing
conges-
tion
can
be
signaled
to
the
user
in
the
form
of
back-
ward
explicit congestion notification (BEeN)
and
forward
explicit
congestion
notification
(FECN).
Frame Relay Forum
FRF.
An
international
profes-
sional
association
of

corporations,
vendors,
carriers,
and
consultants
promoting
the
Frame
Relay
network-
ing
technology,
and
supplying
commercial
Frame
Relay
products
and
services,
established
in
1991.
The
Forum
develops
and
promotes
specifications
to

sup-
port
the
viability of
Frame
Relay
and
sponsors
inter-
operability
events
for
designers,
manufacturers,
and
vendors
to
test
their
Frame
Relay-based
equipment.
/>Frame
Relay
Forum Implementation
Agreements
IA.
A
series
of

formal,
approved
agreements
(stan-
dards) developed and/or supported
by
the
Frame
Relay
Forum.
The
preceding
chart
gives
abrief
sum-
mary
of
lAs,
organized
somewhat
functionally.
The
documents
may
be
freely
downloaded
from
the

Net.
See
Frame
Relay
Forum
chart.
Frame Relay frame format
The
format
for
a
frame
is
based
on
Link
Access
Protocol
D
(LAP-D)
for
ISDN.
Frames
are
also
known
as
protocol
data
units

Frame Relay Frame Format
012
3
456
7 8
012345678901234567890123456789012345678901234567890123456789012345678901234567890
+ / /
+
I
flag
I
address
I
information
I
FCS
I
flag
I
+ / /
+
1
octet
2
to
4
octets
variable
2
octets

1
octet
Header
Structure
+ +
I
DLCI
upper
I
C/R
I 0 I
+ +
I
DLCI
lower
I
FECN
I
BECN
I
DE
I 1 I
+ +
DLeI
data
link
connection
identifier
C/R
command/response

FECN
forward
explicit
congestion
notification
BEeN
backward
explicit
congestion
notification
DE
discard
eligibility
378
© 2003 by CRC Press LLC
(PDUs).
Frame
Relay
frames
are
similar
to
DXI
and
FUN!.
Flags
are
used
to
indicate

the
beginning
and
end
ofa
frame,
which
may
be
variable
in
length.
The
format
specified
for
a
frame
includes
a I-byte
(8-bit)
flag,
followed
by
2
to
4
header
address
bytes,

followed
by
a
variable
number
of
information
bytes,
followed
by
a
2-byte
CRC
code
(frame
check
se-
quence),
followed
by
a I-byte
flag.
There
are
a
num-
ber
of
possible
configurations

of
the
address
field;
it
may
be
two,
three,
or
four
bytes
in
length,
as
deter-
mined
by
the
extended
address
(E/A)
bit.
Informa-
tion
for
the
Local
Management
Interface

enhance-
ments
is
stored
(e.g.,
DLCI
information)
in
the
frame
header.
FrameRelay installation
Frame
relay
communica-
tions
connection
services
are
generally
available
for
a
monthly
subscriber
fee
or
per-data
rate
from

a
lo-
cal
commercial
provider,
depending
upon
the
speed
of
transmission.
One-time
connect
charges
for
instal-
lation
and
port
configuration
are
common.
Transmis-
sion
speeds
up
to
56-64
Kbps
are

typical,
although
most
vendors
offer
higher
speeds
for
more
money.
In-house
installations
of
Frame
Relay
networks
are
also
available.
Frame Relay physical layer interface
The
specifi-
cation
for
Frame
Relay
does
not
stipulate
particular

physical
connectors
or
cables.
In
practice,
however,
unshielded
twisted
pair
(UTP)
is
commonly
used
in
ISDN
implementations
of
Frame
Relay.
Frame
Relay service
Frame
relay
network
service
consists
ofa
combination
ofhardware,

software,
and
transmission
services.
It
provides
multiple
indepen-
dent
multiplexed
data
links
to
another
destination
or
to
several
destinations
through
a
process
which
is
at
least
as
transparent
as
a

leased
line
and
less
expen-
sive.
See
Frame
Relay
installation.
Frame
Relay, voice over
VoFR.
Frame
relay
tech-
nology
provides
an
opportunity
to
combine
data
and
voice
communications
services
over
the
same

net-
work.
Analysis
of
typical
voice
communications
in-
dicates
that
much
of
it
is
unnecessary
(background
sounds,
pauses,
etc.)
and
can
be
screened
out
before
transmission
over
data
networks.
This

aspect
offers
possibilities
for
processing
and
compression
to
pro-
vide
for
efficient
transfer of
digitally
encoded
voice
conversations.
Initially,
there
was
no
uniform
stan-
dard
for
carrying
voice
over
Frame
Relay

and
vari-
ous
schemes
for
its
implementation
had
been
devel-
oped.
In
July
2001,
the
Frame Relay Forum
an-
nounced
FRF.20,
an
IP
Header
Compression
Imple-
mentation
Agreement
that
defines
packet
encapsu-

lation
and
compression
negotiation
to
facilitate
the
transmission
of
voice
over
IP.
Frame Relay-capable interface device
FRCID.
A
peripheral
device
that
performs
frame
encapsulation
within a
Frame
Relay.
See
bridge, encapsulation,
router.
FrameRelayImplementors Forum
An
association

of
vendors
supporting
standards
of interoperability
for
Frame
Relay
implementations.
A
common
speci-
fication
was
first
introduced
in
1990
based
on
the
standard
proposed
by
the
American
National
Stan-
dards
Institute

(ANSI).
See
Frame
Relay
Forum.
Frame Relay
Forum
Implementation Agreements
Number
Date
Description
FRF.6
Mar.
1994
Service
Customer
Net-
work Management Imple-
mentation
FRF.19
Mar.
2001
Operations,
Adminis-
tration and Maintenance
Implementation
FRF.17
Jan.
2000
Privacy Implementa-

tion
FRF.12
Dec.
1997
Fragmentation
Imple-
mentation
FRF.13
Aug.
1998
Service
Level
Defini-
tions
Implementation
FRF.l4
Dec.
1998
Physical Layer inter-
face
Implementation
FRF.l.2
Apr.
2000
User-to-Network
(UNI)
Implementation
FRF.4.1
Jan.
2000

User-to-Network In-
terface
(UNI)
Implementa-
tion
FRF.2.1
July
1995
Network-to-Network
Interface
(NNI)
Implementa-
tion
FRF.lO.l
Sept.
1996
Network-to-Network
SVC
Implementation
FRF.18
Apr.
2000
Network-to-Network
FR/
ATM
SVC
Service
Inter-
working
Implementation

FRF.5
Dec.
1994
Frame Relay/ATM
Network Interworking
Implementation
FRF.8.1
Feb.
2000
Frame Relay/ATM
PVC
Service Interworking
Implementation
FRF.7
Oct.
1994
PVC
Multicast
Service
and
Protocol
Description
FRF.l5
Aug.
1999
End-to-End
Multilink
Implementation
FRF.16
Aug.

1999
Multilink UNI/NNI
Implementation
FRF.3.2
Apr.
2000
Multiprotocol
Encap-
sulation
Implementation
FRF.9
Jan.
1996
Data Compression
Over Frame Relay Imple-
mentation
FRF.l1.1
May
1997
Voice
over
Frame
Re-
lay
Implementation
FRF.20
Jun.
2001
IP
Header Compres-

sion
Implementation
frame store A high-capacity digital
video
storage
buffer.
Frame
stores
are
most
commonly
used
in
two
categories
of
applications:
(I)
those
that
require
im-
age
buffering
to
provide
sufficient
speed
for
continuous

379
© 2003 by CRC Press LLC
Fiber
Optics
Illustrated
Dictionary
display
(see
frames
per
second),
such
as
computer
editing
or
display
systems,
and
(2)
those
that
require
image
buffering
in
order
to
create
complex,

compos-
ite,
or
multiple
display
systems
(such
as
video
walls).
In
the
first
instance,
the
device
from
which
the
frames
are
being
displayed
or
the
display
software
may
not
be

fast
enough
to
read
and
display
at
30
or
so
fps.
By
using
a
frame
store,
sufficient
frames
can
be
buffered
in
fast
access
memory
(or
on
a
very
fast

drive)
to
pro-
vide
quick
display
and
the
illusion
of
continuous
motion.
If
the
display
software
creates
unwanted
ef-
fects
on
the
screen
when
loading
the
next
frame,
the
transition

can
sometimes
be
smoothed
with
double-
buffering
or
grabbing
the
next
frame
from
the
frame
store
rather
than
from
a
hard
drive.
In
other
words,
the
new
image
is
preconstructed

in
memory
while
the
current
image
is
being
displayed,
and
the
buffered
image
can
then
be
displayed
instantly
over
the
pre-
vious
frame,
rather
than
reading
in
and
decompress-
ing

the
frame
and
then
displaying
it
line
by
line
over
the
previous
frame.
In
the
second
type
of
application,
a
frame
store
can
help
compose
a
complex
image,
such
as

computer
graphic
effects
for
a
movie,
which
may
have
been
raytraced
one
frame
at
a
time,
but
which,
when
com-
bined
with
footage
of
the
actors,
needs
to
match
the

speed
of
the
action.
A
frame
store
can
also
be
used
as
a
component
of a
video
wall,
say
20
monitors
in
a
four
by
five
grid,
which
shows
1/20th
of

the
actual
image
on
each
monitor.
Since
this
display
takes
some
computing
power
to
split
up
an
image
into
20
sepa-
rate
subimages,
the
image
grid
could
be
segmented
and

prestored,
so
all
the
monitors
display
the
correct
parts
of
the
grid
at
the
same
time.
See
buffer,
frame
buffer,
desktop
video.
Frame
Switching
bearer
service
FSBS.
In
a
sense,

an
enhanced
version
ofFRBS,
in
that
it
includes
the
basic
functions
of
FRBS,
plus
frame
acknowledg-
ments
and
other
error
and
flow
control
services.
It
is
more
similar
to
X.25,

from
which
Frame
Relay
was
derived,
than
the
basic,
streamlined
FRBS
service
and
reintroduces
some
of
the
features
ofX.25.
frames
per
second
A
phrase
describing
display
speed
for
TV
broadcasts,

video,
and
film
animations.
The
two
most
important
aspects
that
determine
this
speed
are human perception and display technology.
Through
persistence
of
vision
and
expectation,
hu-
mans
perceive
still
frames
displayed
quickly
one
af-
ter

the
other
as
motion.
It
requires
only
about
15
to
30
frames
per
second
(depending
upon
the
amount
of
detail
and
speed
of
the
action)
for
these
images
to
appear

to
be
continuous
motion.
Most
animations
are
created
with
24
to
30
frames
per
second.
Since
mo-
tion
media
can
be
displayed
only
at
the
fastest
speed
of
the
display

medium
(usually
a
cathode-ray
tube),
the
technology
also
determines
the
display
rate,
with
speeds
of
15
to
60
fps
being
implemented,
and
about
20
to
30
fps
most
often
used.

See
frame;
frame
rate,
video;
refresh.
framing bit
FB.
A
noninformational
bit
that
can
be
used
for
a
variety
of
signals
in
frame-based
networks.
A
framing
bit
can
signal
the
frame

beginning
or
end
380
and
error
conditions,
and
it
can
be
used
for
synchro-
nization,
depending
upon
the
quantity
and
pattern
of
frames.
In
its
simplest
implementation,
the
framing
bit signals

to
the
receiving equipment
that
a
new
frame
is
about
to
begin.
In
North
America,
Superframe
and
Extended
Super-
frame
standards
are
used
for
implementing
Tl
net-
work
services.
Each
frame

in
aT1
basic
Superframe
(SF)
includes
eight
information
bits
and
one
fram-
ing
bit.
In
SF,
there
are
two
types
of
framing
bits:
ter-
minal
framing
(Ft)
and
signaling
framing

(Fs)
bits.
In
Extended
Superframe
(ESF),
there
are
three
types
of
framing
bits:
frame
pattern
sync
(Fps),
data
link
(DL),
and
cyclic
redundancy
check
(CRC-6).
The
datalink
framing
bits
differ

somewhat,
depending
upon
whether
ESF
is
implemented
according
to
ANSI
or
AT&T
standards.
The
ANSI
format
provides
for
the
transmission
ofa
Performance
Report
Message
(PRM)
that
allows
actual
performance
to

be
com-
pared
with
established
thresholds
and
an
alert
to
be
generated
if
anomalous
conditions
are
detected.
By
evaluating
the
pattern
of
framing
bits
in
a
series
of
frames,
synchronization

can
be
established.
In
for-
mats
such
as
DS-l
C,
a
framing
bit
can
be
stuffed
to
generate
26-bit
information
units
allowing
for
syn-
chronization
and
framing.
franchise A
government
granted

right
to
offer
com-
munity
public
right-of-way
for
exclusive
commercial
communications
services,
such
as
phone
services
or
cable
broadcast
services.
The
franchise
fees,
or
a
por-
tion
of
them,
may

be
used
by
local
government
agen-
cies,
a
portion
of
which
may
be
allocated
to
local
Des-
ignated
Access
Providers
(DAPs)
for
facilities
fund-
ing.
Some
of
the
earliest
local

phone
companies
may
be
partially
exempt
if
they
gained
their
exclusivity
prior
to
regulation
(grandfathering).
Franklin, Benjamin (1706-1790)
An
American
businessman
(printer),
statesman,
scientist,
and
phi-
losopher
who
did
numerous
experiments
in

electric-
ity
and
printing.
He
shared
his
discoveries
openly
and
coined
many
of
the
terms
now
used
to
describe
me-
chanics
and
electricity.
He
called
vitreous
electric-
ity,
demonstrated
by

rubbing
glass
with
silk,positive
electricity,
and
resinous
electricity,
demonstrated
by
rubbing
amber
with
wool,
negative
electricity.
He
did
experiments with lightning
and
stored electrical
charges
in
a
device
called
a
Leyden
jar,
and

he
es-
tablished
that
man-made
electricity
and
atmospheric
electricity
had
the
same
properties.
These
experi-
ments
were
enthusiastically
received
and
replicated
throughout
Europe,
spurring
much
interest
and
de-
velopment
in

the
field
of
electricity.
Ben
Franklin
also
developed
some
early
document
duplication
techniques
which
he
used
on
his
own
printing
press
to
help
him
manage
his
voluminous
records
and
correspondence.

Ben
Franklin
was
a
successful
business
owner
at
a
relatively
young
age
and
always
hoped
to
retire
early
to
devote
the
rest
of
his
life
to
scientific
inquiry
and
his

various
hobbies,
but
the
American
Revolution
and
the
overwhelming
public
demand
for
his
diplomatic
skills
kept
him
occupied
for
long
hours
right
up
to
© 2003 by CRC Press LLC
the
time
of
his
death

in
his
mid-80s.
See
electrostatic,
Leyden
jar.
Franklin Institute Asignificant
organizer
and
pro-
moter
of
activities
related
to
general
science,
electrical
education,
professional
development,
and
technologi-
cal
deveiopment
in
electronics.
The
Institute

orga-
nized
many
key
American
and
international
exhibi-
tions
starting
in
the
1800s
and
is
still
well
known
for
its
educational
activities
and
awards
for
excellence.
The
Institute
was
founded

by
Merrick
and
Keating
in
1824
as
The
Franklin
Institute
of
the
State
of
Penn-
sylvania
for
the
Promotion
of
the
Mechanic
Arts
in
honor
of
scientist
and
statesman
Benjamin

Franklin.
Since
1926,
the
Institute
has
been
publishing
the
Journal
of
the
Franklin
Institute.
In
1933
it
began
construction
of
the
F
els
Planetarium
and
has
admin-
istrated
the
Franklin

Institute
Science
Museum
since
1934.
In
the
1990s,
multimedia
theaters
were
added
to
provide
enhanced
educational
presentation
capa-
bilities.
See
Benjamin
Franklin
Institute
(not
affili-
ated).
J
fraud
n.
Deceit,

trickery;
unauthorized
access
or
use,
especially
under
an
assumed
identify,
such
as
a
false
username,
or
through
the
use
of
unauthorized
equip-
ment;
misrepresentation
of
identity,
products
or
ser-
vices,

especially
for
monetary
gain.
Unfortunately,
fraud
is
now
rampant
on
the
Internet.
A
criminal
with
fraudulent
intent
can
contact
millions
of
potential
victims
in
seconds
at
minimal
cost.
There
are

many
different
types
of
fraud
on
computer
networks.
Fraudulent
vendors
use
names
that
sound
or
look
like
recognized
businesses
and
create
copy-
cat
Web
sites
selling substandard products
(or
no
products
at

all).
They
use
email
with
embedded
Web
page
links
to
fool
people
into
thinking
they
are
veri-
fying
their
passwords
on
financial
sites
when
in
fact
a
Trojan
horse
program

is
capturing
their
passwords
or
credit
card
numbers.
Fraudsters
also
use
fictitious
email
addresses,
anonymous
emailers,
and
elaborate
mail
routing
to
obscure
their
locations
and
identities.
Naive
users,
especially teenagers, children, senior
citizens,

or
adults
from
small
communities,
are
be-
ing
defrauded
on
a
massive
scale
by
Internet-based
get
rich/pyramid/multilevel
marketing
schemes,
fake
contests,
promises
of
off-shore
commission
profits,
black
and
gray
market

pharmaceuticals,
videos,
and
CDs,
identity
and
credit
card
number
theft,
and
so-
licitations
to
patronize
illegal
pornographic
sites.
Un-
solicited
bulk
email
(spam)
is
one
of
the
primary
ve-
hicles

used
by
fraudulent
companies
to
contact
and
negotiate
with
large
numbers
of
potential
victims
to
perpetrate
these
crimes.
Many
of
these
schemes
are
so
sophisticated
that
it
may
be
difficult,

even
for
a
computer
professional,
to
recognize
the
deceit.
Many
existing
laws
should
be
sufficient
to
protect
victims
from
Internet
fraud,
but
existing
black
market,
theft,
piracy,
embezzle-
ment,
pornography,

and
false
advertising
laws
(which
cover
the
majority
ofInternet-related
crime)
are
dif-
ficult
to
enforce
unless
resources
for
law
enforcement
and
consumer
education
are
increased.
http://www
l.ifccfbi.gov/
Fraunhofer region
In
an

antenna,
a
region
of
the
field
from
which
the
energy
flow
proceeds
as
though
emanating
from
a
point
source
near
the
antenna,
also
called
far-field
region.
It
is
considered
to

be
one
of
three
basic
regions
without
distinct
transition
bound-
aries
that
are
identified
as
you
move
away
from
an
antenna
source.
The
Fraunhofer
region
is
the
one
far-
thest

from
the
source
beginning
at
a
point
where
the
angular
field
distribution
is
considered
to
be
indepen-
dent
of
the
distance
from
the
antenna.
See
Fresnel
region.
Fraunhoferspectrum
The
portion

of
the
solar
spec-
trum
visible
to
humans,
i.e.,
the
portion
where
the
spectral
absorption
lines
can
be
clearly
seen.
The
dark
lines
have
come
to
be
known
as
Fraunhofer

lines.
Fraunhofer
observed
that
the
range
of
spectral
lines
varied
depending
upon
which
celestial
body
was
the
source
of
the
light.
This
information
was
valuable
in
that
it
led
to

observations
about
light
emanating
from
stars
with
different
chemical
compositions,
allowing
scientists
to
analyze
the
composition
of
bodies
in
our
universe
from
a
distance.
The
Fraunhofer
spectrum
can
be
taken

as
a
baseline
reference
against
which
spec-
tral
shifts
can
be
compared.
See
Wallaston,
William.
Fraunhofer, Joseph von (1787-1826) A
German
physicist
who
was
skilled
at
applied
optics
and
lens
design.
As
a scientist,
he

applied
his
knowledge
to
the
study
of
the
Sun,
its
spectra,
and
the
diffraction
of
light.
He
systematically
set
about
measuring
the
position
of
hundreds
ofsolar
spectral
lines
and
clas-

sified
the
most
prominent
lines.
He
then
developed
a
diffraction
grating
and
a
general
grating
equation
for
measuring
the
wavelengths
of
colors
and
of
lines
in
the
dark
spectrum.
Various

aspects
of
spectral
nomen-
clature
are
named
after
Fraunhofer.
FRBS
Frame
Relaying bearer
service.
See
Frame
Relay.
Free Software Foundation
FSF.
A
Massachusetts-
based
association
committed
to
the
development,
ac-
ceptance,
and
promotion

of
open,
free
software
stan-
dards
and
applications
to
benefit
the
world
at
large.
The
freedom
to
copy
and
distribute
software,
and
the
freedom
to
modify,
enhance,
and
improve
software

are
encouraged
by
the
FSF.
Thus,
the
programming
and
user
communities
benefit
by
the
availability of
constantly
improving
software
and
standards,
and
programmers
have
a
broad,
ready
base
of
software
from

which
to
learn
and
to
improve
their
skills.
The
FSF
has
developed
the
integrated
GNU
software
system,
which
includes
assemblers,
compilers,
and
more. Donations
to
the
FSF
are tax deductible.
/>free-space optics FSO. A
term
for

optical
transmis-
sion technologies that
do
not require a physical
waveguide
such
as
a
fiber
optic
cable.
An
infrared
remote
television control
is
an
example
of a
free-
space
transmission
device
that
proj
ects
data
through
line-of-sight "free

space."
Free-space
optics
is
pro-
moted
as
a
means
of
completing
"the
last
mile"
which
is
the
distance
from
major
optical
backbone
transmis-
sion
services
that
separates
most
homes
and

busi-
nesses
in
the U.S.
from
established light-based
381
© 2003 by CRC Press LLC