Method, apparatus and computer program to dynamically adjust segmentation at a protocol layer, such as at the medium access control (MAC) layer

Abstract

In one exemplary aspect thereof the invention provides a method that operates to receive information through at least one input of a protocol layer packet segmentation unit and to dynamically vary packet segment size in accordance with the received information prior to transmission to a receiver. The information received through the at least one input may include information related to channel quality for a channel through which packet data are transmitted to the receiver. The information received through the at least one input may also be or may include information received from at least one of a higher protocol layer or a lower protocol layer.

Full text

(12)
United
States
Patent
Frederiksen
et
al.
US007817667B2
US
7,817,667
B2
Oct.
19,
2010
(10)
Patent
No.:
(45)
Date
of
Patent:
(54)
(75)
(73)
(*)
(21)
(22)
(65)
(60)
(51)
(52)
(58)
(56)
2001/00
15956
A1
METHOD,
APPARATUS
AND
COMPUTER
PROGRAM
TO
DYNAMICALLY
ADJUST
SEGMENTATION
ATA
PROTOCOL
LAYER,
SUCH
AS
AT
THE
MEDIUM
ACCESS
CONTROL
(MAC)
LAYER
Inventors:
Frank
Frederiksen,
Klarup
(DK);
Preben
Mogensen,
Gistrup
(DK);
Jussi
Kahtava,
Tokyo
(JP);
Mika
P.
Rinne,
Espoo
(FI)
Assignee:
Nokia
Corporation,
Espoo
(FI)
Notice:
Subject
to
any
disclaimer,
the
term
of
this
patent
is
extended
or
adjusted
under
35
U.S.C.
154(b)
by
971
days.
Appl.
No.:
11/412,599
Filed:
Apr.
26,
2006
Prior
Publication
Data
|US
2006/0245452
A1
Nov.
2,
2006
Related
U.S.
Application
Data
Provisional
application
No.
60/676,246,
filed
on
Apr.
29,
2005.
Int.
Cl.
H04.J.
3/24
(2006.01)
U.S.
Cl.
.......................................
370/474;
370/229
Field of
Classification
Search
.........
370/229–236,
370/470
476
See
application
file
for
complete
search
history.
References
Cited
|U.S.
PATENT
DOCUMENTS
8/2001
Ono
...........................
370/229
2002/0065093
A1
*
2002/01866.75
A1
*
5/2002 Yi
et
al.
......................
455/517
12/2002
Otting
et
al.
......
...
370/337
...
370/338
2003/0152058
A1*
8/2003
Cimini
et
al.
.....
-
2004/0120300
A1*
6/2004
Saquib
.............
...
370/342
2004/014
1525
A1
*
7/2004
Bhushan
et
al.
... ...
370/473
2004/0254779
A1*
12/2004
Wang
et
al.
...................
703/27
2005/0047346
A1*
3/2005
Terry
et
al.
....
...
370/236
2005/0089084
A1
4/2005
Mahany
.....
...
375/130
2006/0056443
A1*
3/2006
Tao
et
al.
....
...
370/462
2006/0153232
A1*
7/2006
Shvodian
...
...
370/468
2007/0087782
A1
*
4/2007
Pen
............................
455/557
FOREIGN
PATENT
DOCUMENTS
EP
134
1336
A1
OTHER
PUBLICATIONS
Kwan
et
al.,
“Analysis
of
the
Adaptive
Modulation
and
Coding
Algo
rithm
with
the
Multicode
Transmission”
Sep. 24-28,
2002,
2002
IEEE
56”
Vehicular
Technology
Conference,
VTC
2002-Fall.
Pro
ceedings,
vol.
4,
pp.
2007-2011.
9/2003
*
cited
by
examiner
Primary
Examiner—Ricky
Ngo
Assistant
Examiner—Gary
Mui
(74)
Attorney,
Agent,
or
Firm—Harrington
&
Smith
(57)
ABSTRACT
In
one
exemplary
aspect
thereof
the invention
provides a
method
that
operates
to
receive
information
through
at
least
one
input
of
a
protocol
layer
packet
segmentation
unit
and
to
dynamically
vary
packet
segment
size
in
accordance
with
the
received
information
prior
to
transmission
to
a
receiver.
The
information
received
through
the
at
least
one
input
may
include
information
related
to
channel
quality
for
a
channel
through
which
packet
data
are
transmitted
to
the
receiver.
The
information
received
through
the
at
least
one
input
may
also
be
or
may
include
information
received
from
at
least
one
of a
higher
protocol
layer
or
a
lower
protocol
layer.
53
Claims,
3
Drawing
Sheets
[P
PACKET
|P
PACKET
=l—º
L2
SDU
HEADER
COMPRESSION
"..
|PCS
QPDU
(QUALITY
PDU)
CONTROL
PDU
(CH)
H
L2
SECMENT
NUMBER
SH
SH
SH SH
SH
DATA
PDU
MACSDU
H
L2
RETRANSMISSIONS
|
|
J
}
L1
L1
RETRANSMISSIONS

817,667
B2
9
US
7
Sheet 2
of
3
Oct.
19,
2010
U.S.
Patent
XIN?T0||
XÀJOMIEN"
|SSBITERJINA

U.S.
Patent
Oct.
19,
2010
Sheet
3
of
3
US
7,817,667
B2
FROM
L3
20
PACKET
SCHEDULER
MEASUREMENT
INPUT(S)
—ST-a
PART
OF
L2
SEGMENTATION
UNIT
UE
\–V—’
J5
-->|
ADAPTATION
39,0THER
10
ALGORITHM
INPUT(S)
º
*
1
º
e.g.
NODE
B,12
FIG.3
RECEIVE
INFORMATION
THROUGH
AT
LEAST
ONE
INPUT
(35,
37)
AT
MEDIUM
ACCESS
CONTROL
(MAC)
PROTOCOL
LAYER
PACKET
SEGMENTATION
UNIT
(30)
DYNAMICALLY
WARY
PACKET
SEGMENT
SIZE
IN
ACCORDANCE
WITH
THE
RECEIVED
INFORMATION
PRIOR
TO
TRANSMISSION
TO
A
RECEIVER
FIG.4

US
7,817,667
B2
1
METHOD,
APPARATUS
AND
COMPUTER
PROGRAM
TO
DYNAMICALLY
ADJUST
SEGMENTATION
ATA
PROTOCOL
LAYER,
SUCH
AS
AT
THE
MEDIUM
ACCESS
CONTROL
(MAC)
LAYER
CLAIM
OF
PRIORITY
FROM
COPENDING
PROVISIONAL
PATENT
APPLICATION
This
patent
application
claims
priority
under
35
U.S.C.
$119(e)
from
Provisional
Patent
Application
No.
60/676,
246,
filed
Apr.
29,
2005,
the
disclosure
of
which
is
incorpo
rated
by
reference
herein
in
its
entirety.
TECHNICAL
FIELD
The
exemplary
embodiments
of
this
invention
relate
gen
erally
to
wireless
communications
networks,
systems,
meth
ods
and
computer
programs
and,
more
specifically,
relate
to
wireless
digital
communications
systems
that
transmit
packet-based
data
from
a
sender
to
a
receiver.
BACKGROUND
In
a
packet-based
wireless
communications
system
the
system
receives
packets
from
an
upper
layer
(for
example,
from
an
Internet
Protocol
(IP)
layer).
These
packets
need
then
be
transmitted
over
a
wireless
(e.g.,
cellular
mobile)
channel,
which
may
offer
different
and
time
varying
instantaneous
data
rates
to
a
specific
user.
Possible
reasons
for the
variations
in
the
data
rate
may
include:
different
quality
of
service
(QoS)
requirements,
different
instantaneous
channel
conditions,
and
also
previously
sustained
data
rates.
However,
an
impor
tant
point
to
consider
is
that
data
packets
received
from
the
upper
layer(s)
should
be
split
(or
partitioned
or
segmented)
into
smaller
data
units
so
as
to
fit
into
the
instantaneous
data
capacity
on
the
physical
channel.
For
this
to
occur,
the
packets
are
segmented
such
that
the
smallest
segment
size
fits
into
the
lowest
resolution
provided
by
the
physical
layer.
An
impor
tant
reason
for
the
presence
of
the
segmentation
is
that
by
requiring
the
segments
to
have
a
fixed
size,
there
exists
a
well-defined
interface
between
the
Medium
Access
Control
(MAC)
layer
and
the
Physical
layer.
However,
the
inventors
have
realized
that
the
conventional
static
segmentation
size
places
limitations
and
additional
requirements
on
the control
signaling
for
the
MAC
layer,
and
may
also
reduce
the
scheduling
and
link
adaptation
flexibility
at
the
physical
layer.
SUMMARY
OF
THE
EXEMPLARY
EMBODIMENTS
OF
THIS
INVENTION
The
foregoing
and
other
problems
are
overcome,
and
other
advantages
are
realized,
in
accordance
with
the
exemplary
embodiments
of
this
invention.
In
accordance
with
the
exemplary
embodiments
of
this
invention
there
is
provided
a
method
for
receiving
informa
tion
through
at
least
one
input
coupled
to
a
protocol
layer
packet
segmentation
unit
and
for
dynamically
varying
packet
segment
size in
accordance
with
the
received
information
prior
to
transmission
to
a
receiver.
Further
in
accordance
with
the
exemplary
embodiments
of
this
invention
there
is
provided
a
computer
program
product
that
comprises
a
computeruseable
medium
including
a
com
puter
readable
program,
where
the
computer
readable
pro
gram
when
executed
on
the
computer
causes
the
computer
to
perform
operations
that
include
receiving
information
10
15
20
25
30
35
40
45
50
55
60
65
2
through
at
least
one
input
coupled
to
a
protocol
layer
packet
segmentation
unit
and
dynamically
varying
packet
segment
size
in
accordance
with
the
received
information
prior
to
transmission
to
a
receiver.
Further
in
accordance
with
the
exemplary
embodiments
of
this
invention
there
is
provided
a
device
having
a
first
protocol
layer
outputting
packet
data;
a
second
protocol
layer
coupled
to
the
first
protocol
layer
and
comprising
a
packet
data
sched
uling
unit
and
a
packet
data
segmentation
unit
having
at
least
one
input
for
receiving
information;
and
a
third
protocol
layer
coupled
to
the
second
protocol
layer
for
sending
segmented
packet
data
towards
a
receiver.
The
packet
segmentation
unit
operates
to
dynamically
vary
packet
segment
size,
in
accor
dance
with
the
received
information,
prior
to
transmission
to
the
receiver.
Further
still
in
accordance
with
the
exemplary
embodi
ments
of
this
invention
there
is
provided
a
wireless
commu
nication
system
node,
such
as
a
base
station
or
a
user
equip
ment,
that
includes
a
transmitter
for
transmitting
packet
data
to
a receiver
and
at
least
one
data
processor
coupled
to
the
transmitter
and
operating
under
control
of
a
stored
program
for
implementing
a
Radio
Link
Layer
outputting
packet
data,
a
Medium
Access
Control
layer
coupled
to
the
Radio
Link
Layer
and
comprising
means
for
segmenting
packet
data,
and
a
Physical
layer
coupled
to
the
Medium
Access
Control
layer
for
sending
segmented
packet
data
to
the
receiver via said
transmitter.
The
Medium
Access
Control
layer
comprises
means
for
dynamically
varying
a
size
of
packet
data
segments
output
to
the
Physical
layer
in
accordance
with
at
least
one
of
information
received
from
the
Radio
Link
Layer,
information
received
from
the
Physical
layer,
and
information
available
within
the
Medium
Access
Control
layer.
BRIEF
DESCRIPTION
OF
THE
DRAWINGS
The
foregoing
and
other
aspects
of
the
exemplary
embodi
ments
of
this
invention are
made
more
evident
in
the
follow
ing
Detailed
Description,
when
read
in
conjunction
with
the
attached
Drawing
Figures,
wherein:
FIG.
1
is
a
diagram
that
illustrates
segmentation
of
packets
at
the
MAC
layer.
FIG.
2
is
a
simplified
block
diagram
of
a
wireless
commu
nications
system
that
operates
in
accordance
with
the
exem
plary
embodiments
of
this
invention.
FIG. 3
is
a
simplified
block
diagram
of
a
portion
of
the
wireless
communications
system
shown
in
FIG.
2,
and
that
illustrates
in
further
detail
a
packet
segmentation
unit,
an
adaptation
algorithm
logical
block,
and
a
packet
scheduler
that
cooperate
in
accordance
with
the
exemplary
embodi
ments
of
this
invention.
FIG.
4
is
a
logic
flow
diagram
that
is
illustrative
of
the
operation
of
a
method
in
accordance
with
the
exemplary
embodiments
of
this
invention.
DETAILED
DESCRIPTION
The
exemplary
embodiments
of
this
invention
relate
to
a
segmentation of
packet
data
between
two
protocol
layers
that
are
capable
of
supporting
different
size
data
packets.
One
non-limiting
example
is
L1
and
L2
as
in
the
Universal
Ter
restrial
Radio
Access
Network-Long
Term
Evolution
(UT
RAN-LTE)
cellular
communication
system,
sometimes
referred
to
as
the
“3.9G’”
system.
It is
noted
that
while
the
ensuing
description
is
made
pri
marily
using
an
example
of
the
packet
segmentation
unit
being
disposed
in
the
Medium
Access
Control
(MAC)
proto
collayer,
in
other
embodiments
the
packet
segmentation
unit

US
7,817,667
B2
3
may
be
disposed
in
a
different
protocol
layer,
such
as
in
the
Radio
Link
Control
(RLC)
or
Radio
Network
Layer
(RNL),
or
possibly
even
in
the
PHY
layer.
However,
in
all
of
these
possible
embodiments
it
is
a feature
of
the
exemplary
embodiments
of
the
invention
that
the
segment
size
may
be
varied
according
to
dynamically
changing,
possibly
short
term
requirements
such
as,
but not
limited
to,
varying
throughput/data
rates.
FIG.
1
shows
the
segmentation
of
data
packets
(e.g.,
Inter
net
Protocol
(IP)
packets)
in
the
MAC
layer,
where
PDU
stands
for
Protocol
Data
Unit,
L3
is
Layer
3
(Radio
Network
Layer
(RNL)),
L2
is
the
MAC
layer,
L1
is
Layer
1
(Physical
(PHY)
Layer),
SDU
is
a Service
Data
Unit,
PDU
is
a
Protocol
Data
Unit,
H
is
a
Header,
CRC
is
Cyclic
Redundancy
Check
and
OFDM
symbols
are
Orthogonal
Frequency
Division
Multiplex
symbols.
Note
that
the
L2
segment
numbers
are
added
to
the
SH
(Service
Headers)
when
forming
the
L1
SDU.
The
“primitives”
shown
in
FIG.1
representanability
of
L1
to
inform
L2
of
the
segment
size
that
is
available,
so
that
MAC
segmentation
is
performed
accordingly
(roughly).
L1
may
further
fit
the
segments
received
from
L2
to
payload
allocations
by
rate
matching
techniques.
In general,
a small
segment
size
provides
large
scheduling
and
link
adaptation
flexibility,
even
for
low
data
rates.
How
ever,
for
high
instantaneous
data
rates
many
segments
need
to
be
transmitted,
and
thus
a
segmentation
ID
number
needs
to
be
able
to
express
relatively
high
resolution,
resulting
in
larger
communications
overhead
(at
least
for
the
reason
that
more
bits
need
to
be
sent
to
express
the
segmentation
ID).
In
general,
a
large
segment
size
provides
low
scheduling
and
link
adaptation
flexibility
for
low
data
rates.
However,
for
high
instantaneous
data
rates
some
segments
need
to
be
trans
mitted,
but
as
the
segments
are
relatively
large,
the
segmen
tation
ID number
resolution
can
potentially
be
relatively
low,
resulting
in
reduced
overhead.
In
either
case,
if
the
segmentation
size
is
maintained
at
a
constant
value
it
becomes
difficult
to
achieve
the best
or
near
optimum
value
for
the
segmentation
size.
The
exemplary
embodiments
of
this
invention
provide
a
technique
to
adap
tively
adjust
the
segmentation
size
such
that
a
best
compro
mise
between
link
adaptation
flexibility
and
overhead
is
achieved.
The
exemplary
embodiments
of
this
invention
may
use
only
L2
information.
By
providing
lower
resolution
when
possible,
the signaling
can
be
reduced
accordingly,
and
the
number
of
required
signaling
bits
can
be
reduced.
Reference
is
made
to
FIG.
2
for
illustrating
a
simplified
block
diagram
of
various
electronic
devices
that
are
suitable
for
use
in
practicing
the
exemplary
embodiments
of
this
invention.
In
FIG.
2
a
wireless
network
1
is
adapted
for
communication
with
a
UE
10
via
a
Node
B
(also
referred
to
as
a
base
station)
12.
The
network
1
may
include
at least
one
network
control
function
(NCF)
14.
The
UE
10
includes
a
data
processor
(DP)
10A,
a
memory
(MEM)
10B
that
stores
a
program
(PROG)
10C,
and
a
suitable
radio
frequency
(RF)
transceiver
10D
for
bidirectional
wireless
communications
with
the
Node
B12,
which
also
includes
a
DP12A,
a
MEM
12B
that
stores
a
PROG
12C,
and
a
suitable
RF
transceiver
12D.
The
Node
B12
is
coupled
via
a
data
path
13
to
the
NCF
14
that
also
includes
a
DP
14A
and
a
MEM
14B
storing
an
associated
PROG
14C.
At
least
one
of
the
PROGs
10C
and
12C
is
assumed
to
include
program
instructions
that,
when
executed
by
the
associated
DP
enable
the
electronic
device
to
operate
in
accordance
with
the
exemplary
embodiments
of
this
invention,
as
will
be
discussed
below
in
greater
detail.
The
UE
10
is
assumed
to
include
and
implement
a
protocol
stack
10E
containing
at
least
layers
L1
(PHY,
Physical),
L2
(RLL,
Radio
Link
Layer,
containing
the
MAC
functionality)
10
15
20
25
30
35
40
45
50
55
60
65
4
and
L3
(RNL,
Radio
Network
Layer),
and
typically
higher
layers
as
well
(e.g.,
an
IPlayer).
The
Node
B12
is
assumed
to
include
and
implement
a
protocol
stack
12E
also
containing
at
least
layers
L1
(PHY),
L2
(RLL)
and
L3
(RNL),
and
typically
also
the
higher
layers
as
well
(e.g.,
an
IP
layer).
In
general,
the
various
embodiments
of
the
UE
10
can
include,
but
are
not
limited
to,
cellular
telephones,
personal
digital
assistants
(PDAs)
having
wireless
communication
capabilities,
portable
computers
having
wireless
communi
cation
capabilities,
image
capture
devices
such
as
digital
cameras
having
wireless
communication
capabilities,
gam
ing
devices
having
wireless
communication
capabilities,
music
storage
and
playback
appliances
having
wireless
com
munication
capabilities,
Internet
appliances permitting
wire
less
Internet
access
and
browsing,
as
well
as portable
units
or
terminals
that
incorporate
combinations
of such
functions.
The
embodiments
of
this
invention
may
be
implemented
by
computer
software
executable
by
the
DP12A
of
the
Node
B,
and/or
by
the
DP10A
of
the
UE
10,
or
by
hardware,
or
by
a
combination
of
software
and
hardware.
The
MEMs
10B,
12B
and
14B
may
be
of
any
type
suitable
to
the
local
technical
environment
and
may
be
implemented
using
any
suitable
data
storage
technology,
such
as
semicon
ductor-based
memory
devices,
magnetic
memory
devices
and
systems,
optical
memory
devices
and
systems,
fixed
memory
and removable
memory.
The
DPs
10A,
12A
and
14A
may
be
of
any
type
suitable
to
the
local
technical
environ
ment,
and
may
include
one
or
more
of
general
purpose
com
puters,
special
purpose
computers,
microprocessors,
digital
signal
processors
(DSPs)
and
processors
based
on
a
multi
core
processor
architecture,
as
non-limiting
examples.
Reference
is
now
made
to
FIG.
3,
which
illustrates
in
greater
detail
a
portion
of
the
Node
B12
of
FIG.
2.
Based
on
a
number
of
segments
scheduled
for
a
single
mobile
terminal
(MT),
or
more
generally
for
the
UE
10,
a
network
packet
scheduler
(PS)
20,
that
is
coupled
to
a
segmentation
unit
(SU)
30
that
operates
in
accordance
with an
adaptation
algorithm
35,
also
referred
to
as
a
segmentation
control
unit
that
is
an
aspect
of
the
exemplary
embodiments
of
this
invention,
ana
lyzes
overhead
and
link
adaptation
flexibility,
and
adjusts
(dynamically)
the
packet
segmentation
size
to
achieve
a
cur
rently
“best”
segmentation
unit
operating
point.
The
principles
of
operation
of
the
adaptation
algorithm
25
are
now
illustrated
by
way
of
an
example.
Assuming
the
case
of
a
single
user
(UE
10),
assume
further
that
the
segmentation
size
for
the
user
is
16
bytes,
and
the
maximum
number
of
segments
that
can
be
used
in
the
total
system
is
4096
segments
(i.e.,
segment
header
size=12
bits).
Due
to
different
Hybrid
Automatic
Retransmission
Request
(H-ARQ)
channels
and
delays,
this
transforms
into
a
maxi
mum
value
of
approximately
64
segments
within a
single
Transmit
Time
Interval
(TTI).
Assume now
that
the
UE
10
is
experiencing
good
channel
conditions
such
that
the
maximum
value
of
64
segments
would
almost
always
be
used.
In
this
case
the
adaptive
algo
rithm
35
detects
through
one
or
more
inputs
(referred
to
as
“measurement
input(s)”
37
in
FIG.
3),
the
existence
of
the
good
channel
conditions
and
adjusts
the
segmentation
size
such
that
the
segmentation
size
is
increased
by
some
factor,
such
as
by
a
factor
of
at
least
two.
A
non-limiting
example
of
an
input
that
the
adaptation
algorithm
35
may
consider
is
a
number
of
packets
scheduled
for
the
UE
10,
as
it
may
be
assumed
that
the
PS20
will
schedule
more
packets
for
the
UE
10
during
good
channel
conditions.
If,
on
the
other
hand,
the
UE
10
is
experiencing
poor
channel
conditions,
the
PS
20
may
be
assumed
to
schedule
only
a
few
packets
at
a
time.
In
this
case
the
adaptation

US
7,817,667
B2
7
Furthermore,
some
of
the
features
of
the
exemplary
embodiments
of
this
invention
may
be
used
to
advantage
without
the
corresponding
use
of
other
features.
As
such,
the
foregoing
description
should
be
considered
as
merely
illus
trative
of
the
principles,
teachings,
examples
and
embodi
ments
of
this
invention,
and
not
in
limitation
thereof.
What
is
claimed
is:
1.
A
method,
comprising:
receiving
information
through
at
least
one
input
at
a
medium
access
control
protocol
layer
for
a
packet
seg
mentation
unit;
and
dynamically
varying
packet
segment
size
in
accordance
with
the
received
information
and
physical
layer
pay
load
and
in
accordance
with
data
received
by
the
medium
access
control
protocol
layer
from
a
lower
layer
prior
to
transmission,
via
cellular
communications,
to
a
receiver.
2.
The
method
of
claim
1,
where
the
information
received
through
the
at
least
one
input
is
comprised
of
information
related
to
channel
quality
for a
channel
through
which
packet
data
are
transmitted
to
the
receiver.
3.
The
method
of
claim
2,
where
the
channel
quality
infor
mation
is
derived
from
at
least
a
number
of
data
packets
scheduled
for
transmission
to
the
receiver.
4.
The
method
of
claim
2,
where
the
channel
quality
infor
mation
is
derived
from
at
least
an
occurrence
of
re-transmis
sions
of
packet
data.
5.
The
method
of
claim
2,
where
the
channel
quality
infor
mation
is
derived
from
at
least
a
frequency
of
re-transmis
sions
of
packet
data.
6.
The
method
of
claim
1,
where
the
information
received
through
the
at
least
one
input
is
comprised
of
information
received
from
a
higher
protocol
layer.
7.
The
method
of
claim
6,
where
the
information
received
from
the
higher
protocol
layer
is
comprised
of
information
descriptive
of
a
segment
size
used
by
the
higher
protocol
layer.
8.
The
method
of
claim
6,
where
the
information
received
from
the
higher
protocol
layer
is
comprised
of
information
descriptive
of
a
maximum
segment
size
defined
per
internet
protocol
flow.
9.
The
method
of
claim
6,
where
the
information
received
from
the
higher
protocol
layer
is
comprised
of
information
descriptive
of
packet
segment
sizes
in
a
transmission
buffer.
10.
The
method
of
claim
1,
where
the
information
received
through
the
at
least
one
input
is
comprised
of
information
received
from
a
lower
protocol
layer.
11.
The
method
of
claim
1,
where
dynamically
varying
packet
segment
size
varies
the
segment
size
by
a
predeter
mined
amount.
12.
The
method
of
claim
1,
where
for
a
packet
size
below
a
threshold
packet
size,
the
packet
is
passed
to
a
lower
protocol
layer
without
being
segmented.
13.
The
method
of
claim
1,
where
the
receiver
is
comprised
of
user
equipment.
14.
The
method
of
claim
1,
where
the
receiver
is
comprised
of
a
base
station.
15.
The
method
of
claim
1,
further
comprising
signaling
a
currently
selected
packet
segment
size
to
the
receiver.
16.
The
method
of
claim
1,
further
comprising
performing
an
analysis
of
overhead
and
link
adaptation
flexibility
and
using
the
performed
analysis
when
dynamically
varying
the
packet
segment
size.
17.
The
method
of
claim
1,
wherein
the
packet
segment
size
is
dynamically
varied
by
a
predetermined
factor.
18.
A
non-transitory
computer
program
product
compris
ing
a
computer
useable
medium
including
a
computer
read
8
able
program,
wherein
the
computer
readable
program
when
executed
on
the
computer
causes
the
computer
to
perform
operations
comprising:
receiving
information
through
at
least
one
input
at
a
5
medium
access
control
protocol
layer
for
a
packet
seg
mentation
unit;
and
dynamically
varying
packet
segment
size
in
accordance
with
the
received
information
and
physical
layer
pay
load
and
in
accordance
with
data
received
by
the
medium
access
control
protocol
layer
from
a
lower
layer
prior
to
transmission,
via
cellular
communications,
to
a
receiver.
19.
The
computer
program
product
of
claim
18,
where
the
information
received
through
the
at
least
one
input
is
com
15
prised
of
information
related
to
channel
quality
for
a
channel
through
which
packet
data
are
transmitted
to
the
receiver.
20.
The
computer
program
product
of
claim
19,
where
the
channel
quality
information
is
derived
from
at
least
one
of
a
number
of
data
packets
scheduled
for
transmission
to
the
20
receiver,
an
occurrence
of
re-transmissions
of
packet
data,
and
a
frequency
of
re-transmissions
of
packet
data.
21.
The
computer
program
product
of
claim
18,
where
the
information
received
through
the
at
least
one
input
is
com
prised
of
information
received
from
a
higher
protocol
layer.
22.
The
computer
program
product
of
claim
21,
where
the
information
received
from
the
higher
protocol
layer
is
com
prised
of
information
that
is
at
least
one of
descriptive
of a
segment
size
used
by
the
higher
protocol
layer,
descriptive
of
a
maximum
segment
size
defined
per
internet
protocol
flow,
and
descriptive
of
packet
segment
sizes
in
a
transmission
buffer.
23.
The
computer
program
product
of
claim
18,
where
the
information
received
through
the
at
least
one
input
is
com
prised
of
information
received
from
a
lower
protocol
layer.
24.
The
computer
program
product
of
claim
18,
where
the
operation
of
dynamically
varying
packet
segment
size varies
the
segment
size
by
a
predetermined
amount.
25.
The
computer
program
product
of
claim
18,
where
for
a
packet
size
below
a
threshold
packet
size,
the
packet
is
passed
to
a
lower
protocol
layer
without
being
segmented.
26.
The
computer
program
product
of
claim
18,
further
comprising performing an
analysis
of
overhead
and
link
adaptation
flexibility
and
using
the
performed
analysis
when
dynamically
varying
the
packet
segment
size.
27.
The
computer
program
product
of
claim
18,
wherein
the
packet
segment
size
is
dynamically
varied
by
a
predeter
mined
factor.
28.
A
device,
comprising:
a
first
protocol
layer
outputting
packet
data;
a
second
protocol
layer
configured
to
communicate
with
the
first
protocol
layer
and
comprising
a
packet
data
scheduling
unit
and
a
packet
data
segmentation
unit
having
at
least
one
input
at
a
medium
access
control
for
receiving
information;
and
a
third
protocol
layer
configured
to
communicate
with
the
second
protocol
layer
for
sending
segmented
packet
data,
via
cellular
communications,
towards
a
receiver;
where
said
packet
segmentation
unit
operates
to
dynamically
vary
packet
segment
size,
in
accordance
with
the
received
information
and
physical
layer
pay
load
and
in
accordance
with
data
received
by
the
second
protocol
layer
from
a
third
protocol
layer,
prior
to
trans
mission
to
the
receiver,
wherein
the
third
protocol
layer
is
a
lower
layer
than
the
second
protocol
layer.
29.
The
device
of
claim
28,
where
the
information
received
through
the
at
least
one
input
is
comprised
of
information
10
25
30
35
40
45
50
55
60
65

US
7,817,667
B2
9
related
to
channel
quality
for a
channel
through
which
packet
data
are
transmitted
to
the
receiver.
30.
The
device
of
claim
29,
where
the
channel
quality
information
is
derived
from
at
least
a
number
of
data
packets
scheduled
for
transmission
to
the
receiver
by
the
packet
scheduling
unit.
31.
The
device
of
claim
29,
where
the
channel
quality
information
is
derived
from
at
least
an
occurrence
of
re
transmissions
of
packet
data.
32.
The
device
of
claim
29,
where
the
channel
quality
information
is
derived
from
at
least
a
frequency
of
re-trans
missions
of
packet
data.
33.
The
device
of
claim
28,
where
the
information
received
through
the
at
least
one
input
is
comprised
of
information
received
from
the
first
protocol
layer.
34.
The
device
of
claim
33,
where
the
information
received
from
the
first
protocol
layer
is
comprised
of
information
descriptive
of
a
segment
size
used
by
the
first
protocol
layer.
35.
The
device
of
claim
33,
where
the
information
received
from
the
first
protocol
layer
is
comprised
of
information
descriptive
of
a
maximum
segment
size
defined
per
internet
protocol
flow.
36.
The
device
of
claim
33,
where
the
information
received
from
the
first
protocol
layer
is
comprised
of
information
descriptive
of
packet
segment
sizes
in
a
transmission
buffer.
37.
The
device
of
claim
28,
where
the
information
received
through
the
at
least
one
input
is
comprised
of
information
received
from
the
third
protocol
layer.
38.
The
device
of
claim
28,
where
said
segmentation
unit
dynamically
varies
packet
segment
size
by
a
predetermined
amount.
39.
The
device
of
claim
28,
where
for
a
packet
size
below
a
threshold
packet
size,
the
segmentation
unit
passes
the
packet
to
the
third
protocol
layer
without
being segmented.
40.
The
device
of
claim
28,
where
the
receiveris
comprised
of
user
equipment.
41.
The
device
of
claim
28,
where
the
receiveris
comprised
of
a
base
station.
42.
The
device
of
claim
28,
further
comprising
signaling
a
currently
selected
packet
segment
size
to
the
receiver.
43.
The
device
of
claim
28,
where
said
second
protocol
layer
is
comprised
of
a
medium
access
control
protocol
layer.
44.
The
device
of
claim
28,
wherein
the
packet
segment
size
is
dynamically
varied
by
a
predetermined
factor.
45.
A
wireless
communication
system
node,
comprising:
a
transmitter
configured
to
transmit
via
cellular
communi
cations
packet
data
to
a
receiver;
and
at
least
one
data
processor
configured
to
communicate
with
the
transmitter
and
configured
to
operate
under
control
of
a
stored
program
for
implementing
a radio
link
layer
10
15
20
25
30
35
40
45
10
outputting
packet
data,
a
medium
access
control
layer
configured
to
communicate
with
the
radio
link
layer
and
comprising
means
for
segmenting
packet
data,
and
a
physical
layer
configured
to
communicate
with
the
medium
access
control
protocol
layer
for
sending
seg
mented
packet
data
to
the
receiver via
said
transmitter,
said
medium
access
control layer
comprising
means
for
dynamically
varying
a
size
of
packet
data
segments
out
put
to
said
physical
layer
in
accordance
with
physical
layer
payload
and
at
least
one
of
information
received
from
said
radio
link
layer,
information
received
from
said
physical
layer
by
the
medium
access
control
layer,
and
information
available
within
said
medium
access
control layer
prior
to
transmission
to
the
receiver.
46.
The
wireless
communication
system
node
of
claim
45,
where
said
information
is
indicative
of
at
least
a
quality
of
a
channel
through
which
the
packet
data
is
transmitted
to
the
receiver.
47.
The
wireless
communication
system
node
of
claim
45,
embodied
in
a
base
station.
48.
The
wireless
communication
system
node
of
claim
45,
embodied
in
user
equipment.
49.
The
wireless
communication
system
node
of
claim
45,
where
the
information
available
in
said
medium
access
con
trol
layer
is
obtained
at
least
in
part
from
means
for
schedul
ing
packet
data for
outputting
to
said
physical
layer.
50.
The
wireless
communication
system
node
of
claim
45,
where
the
physical
layer
sends
the
segmented
packet
data
to
the
receiver
as
orthogonal
frequency
division
multiplexing
symbols.
51.
The
wireless
communication
system
node
of
claim
45,
wherein
the
packet
segment
size
is
dynamically
varied
by
a
predetermined
factor.
52.
An
apparatus
comprising:
at
least
one
processor;
and
at
least
one
memory
including
computer
code,
wherein
the
at
least
one
memory
including
computer
code,
along
with
the
processor,
is
configured
to
perform
as
follows:
receive
information
through
at
least
one
input
at
a
medium
access
control
protocol
layer for
a packet
segmentation
unit;
and
dynamically
vary
packet
segment
size
in
accordance
with
the
received
information
and
physical
layer
and
in
accor
dance
with
data
received
by
the
medium
access
control
protocol
layer
from
a
lower
layer
payload
prior
to
trans
mission,
via
cellular
communications,
to
a
receiver.
53.
The
apparatus
of
claim
52,
wherein
the
packet
segment
size
is
dynamically
varied
by
a
predetermined
factor.