experiments in cognitive radio and dynamic spectrum access ... · experiments in cognitive radio...

©2006 The MITRE Corporation. All rights reserved

Exp

eri

men

ts in

Co

gn

itiv

e R

ad

io a

nd

Dyn

am

ic S

pectr

um

Access u

sin

g A

n

On

tolo

gy-R

ule

Hyb

rid

Arc

hit

ectu

re

Allen

Gin

sb

erg

, Jeff

rey D

. P

osto

n, an

d W

illiam

D. H

orn

e

Th

e M

ITR

E C

orp

ora

tio

n

McL

ean

, V

irg

inia

US

A

2


Ba

ck

gro

un

d

�W

hat

is a

rad

io?

�A

nyth

ing

th

at

uti

lizes s

pectr

um

:

,

,

(t

ran

sm

it-r

eceiv

e)

�S

tate

-of-

the-a

rt: Software Defined Radio

(SD

R)

�u

ses s

oft

ware

fo

r th

e m

od

ula

tio

n a

nd

de

mo

du

lati

on

of

wa

ve

form

s

�S

CA

re

fere

nce m

od

el

(CO

RB

A &

PO

SIX

based

)

�S

pectr

um

Allocation

�S

pectr

um

use

reg

ula

ted

by e

ach

nati

on

& i

nte

rnati

on

al tr

eaty

�ke

y g

overn

ing

pri

ncip

le:

avo

id i

nte

rfere

nce

.

�u

se s

tati

c a

llo

cati

on

sch

em

e

-e.g

., A

nalo

g T

V u

ses U

HF

, V

HF

ban

ds, etc

.

�H

as s

pectr

um

beco

me s

carc

e?

�M

ore

an

issu

e o

f in

eff

icie

ncy o

f sta

tic a

llo

cati

on

�th

ere

is p

len

ty o

f u

nu

tili

zed

sp

ectr

um

at

an

y g

ive

n p

lace a

nd

tim

e

�D

yn

am

ic S

pectr

um

Access

�C

ou

ld b

e c

om

pati

ble

wit

h a

llo

cati

on

to

pri

mary

(li

cen

se

d)

users

�A

llo

w s

eco

nd

ary

users

to

acces

s w

hen

pri

mary

is n

ot

usin

g

3


Wh

at

is Cognitive Radio

?

�At least the following:

�D

evic

e a

rch

ite

ctu

re &

in

frastr

uctu

re f

or

dyn

am

ic s

pectr

um

acce

ss

�P

oli

cie

s &

co

nven

tio

ns t

hat

all

ow

CR

s t

o c

oexis

t

�M

an

y r

esearc

h a

pp

roach

es, e.g

., g

am

e t

heo

ry

�O

ur

ap

pro

ach

: u

se s

em

an

tic t

ech

no

log

ies

�W

hy?

�B

uil

d u

po

n D

AR

PA

XG

ap

pro

ach

to

po

licy c

he

ckin

g.

�S

pectr

um

po

lic

y w

ill

evo

lve,

no

t d

isap

pear.

�D

yn

am

ic a

cce

ss m

ust

co

exis

t w

ith

th

ose p

oli

cie

s.

�A

ll r

ad

ios

mu

st

be p

olic

y-c

om

pli

an

t (b

eh

avio

r guidedby

po

lic

y)

�F

orm

al re

pre

se

nta

tio

n o

f p

olic

y a

llo

ws f

lexib

ilit

y,

etc

. in

CR

de

ve

lop

men

t

�R

ad

io t

hat

un

ders

tan

ds p

olicy c

an

do

mo

re

�Knowledge-driven differential-response

4


Ca

se

Stu

dy:

Dyn

am

ic F

req

ue

nc

y S

ele

cti

on

(D

FS

)

�A

llo

ws 5

GH

z w

irele

ss d

evic

es t

o c

oexis

t w

ith

leg

ac

y r

ad

ar

�T

he F

CC

DF

S r

ule

s r

eq

uir

e 2

devic

e t

yp

es:

Maste

r &

Clien

t

�C

lien

t

�m

us

t associate

wit

h a

Mas

ter

befo

re u

sin

g c

ha

nn

el

in b

an

d.

�can

on

ly u

se

ch

an

nel

if M

aste

r sa

ys “

ok

.”

�m

us

t vaca

te c

han

nel

if M

aste

r sen

ds v

acate

sig

nal

�if c

lien

t h

as

rad

ar-

sen

sin

g c

ap

ab

ilit

y,

it m

us

t re

po

rt d

ete

cte

d r

ad

ar

to

asso

cia

ted

mas

ter

(an

d t

hen

va

cate

ch

an

nel)

�M

aste

r

�m

us

t lis

ten

fo

r 60 s

ec f

or

rad

ar

pri

or

to a

llo

win

g f

irs

t u

se o

f ch

an

nel

an

d r

efr

ain

fro

m p

erm

itti

ng

us

e i

f ra

dar

de

tec

ted

�m

on

ito

r fo

r ra

dar

for

ch

an

nels

in

use

�if

rad

ar

de

tecte

d, b

road

cas

t va

cate

sig

na

l to

cli

en

ts.

�C

han

nel

mu

st

be v

aca

ted

wit

hin

10 s

eco

nd

s o

f ra

dar

dete

cti

on

�re

frain

fro

m u

sin

g t

he c

han

ne

l aft

er

rad

ar

de

tecte

d f

or

at

least

30 m

in.

5


Ba

sic

DF

S D

es

ign

Pro

file

s -

Sc

en

ari

os

No

tio

nal R

ad

ar

So

urc

e

Netw

ork

#2 –

“In

ten

ded

beh

avio

r”d

esig

n

Netw

ork

#1 –

“B

are

bo

nes”

desig

n

Master

Client

Stop using

channel 56 now!

I detect a radar signal

Client

Master

Roger. Stop using

channel 56; move to

channel 136.

6


En

ha

nc

ed

DF

S D

es

ign

Pro

file

s -

Sc

en

ari

os

(I

nvo

lvin

g K

no

wle

dg

e-D

riven

Dif

fere

nti

al

Resp

on

se)

No

tio

nal

Rad

ar

So

urc

e

Netw

ork

#2

Netw

ork

#1

Master

Client

Stop using

channel 56 now!

Master

Channel 56

available.

Enhanced DFS Scenario-1: Master-Swapping

I’m switching

masters.

No

tio

nal

Rad

ar

So

urc

e

Netw

ork

Client

Master

Channel 56

available.

Enhanced DFS Scenario-2: Gradient-Surfing

I detect radar on channel

56. I also faintly detect a

master confirm

ing

availability on channel 56.

If I associate with that

master from this location I

will have to report the

radar. I should move

closer to the master

before associating.

7


Pro

toty

pe

Sim

ula

tio

n u

sin

g B

ea

co

n-B

as

ed

S

pe

ctr

um

Ac

ce

ss

�O

WL

On

tolo

gy

�Jen

a r

ule

s

�u

se o

f cu

sto

m b

uilt-

in f

eatu

re

�R

ad

io h

ard

ware

an

d r

ad

io

pro

pag

ati

on

em

ula

ted

in

Java;

�In

term

s o

f D

FS

scen

ari

os

�p

osit

ive b

eac

on

is M

aste

r sig

nali

ng

ch

an

nel

avail

ab

le

�n

eg

ati

ve b

ea

co

n i

s r

ad

ar

sig

nal

(or

maste

r sen

din

g

va

cate

sig

nal)

�“S

em

an

tic b

eaco

ns”

co

uld

be

imp

ort

an

t in

fu

ture

CR

ap

ps

8


Exam

ple

Tacti

cal

Milit

ary

Scen

ari

o

•W

NW

an

d S

RW

(an

d o

ther

tacti

cal w

avefo

rms)

need

sig

nif

ican

t sp

ectr

um

� ��C

om

peti

ng

fo

r sam

e a

va

ilab

le s

pectr

um

!

•E

mb

ed

“co

gn

itiv

e”

mo

du

les

in

to

rad

ios t

o p

rovid

e:

-A

uto

ma

ted

fre

qu

en

cy s

ele

cti

on

&

deco

nfl

icti

on

-A

dap

tive

to

ch

an

ges i

n m

iss

ion

need

s

an

d e

nvir

on

me

nt

JW

NM

Co

mm

Da

tab

as

e

1WNW Network Definition

*values in table examples only

Subnet A

OFDM

1425 Ground Members

Sparse

Low Jamming Threat

Desert Terrain

Subnet B

AJ

150 Ground Mem

bers

Dense

Moderate Jamming Threat

Urban Terrain

2Tab

le Lookup

Number of DOCs

Comm

Database Entry

Subnet A = 4 channels

Subnet B = 9 channels

Sp

ec

tru

m

Ma

na

ge

r

Allowab

le

Frequen

cies

JWNM

Processing

5Assign Frequen

cies

Chan

nels to Subnets

Comm

Database Entry

Frequen

cy Chan

nel Definition

4

Reques

t Frequen

cies based

on number

of ch

annels needed and b

andwidths

supported

by each

SiS.

BE

AM

OF

DM

AJ

LP

I/L

PD

0.025

x

0.15

x

0.3

x

0.6

xx

x

1.2

xx

x

3x

xx

5x

xx

10x

xx

20x

x

30x

x

SiS

Ba

nd

wid

th (

Mh

z)

Pla

tfo

rm

Cate

go

ry

Ty

pe

Nu

mb

er

of

No

des

SparseModerate

Dense

2 - 20

11

1

21 - 60

11

2

61 - 200

12

3

201 - 450

23

4

451 - 800

34

5

801 - 1630

45

6

2 - 20

11

1

21 - 60

11

2

61 - 200

12

3

201 - 450

23

4

451 - 800

34

5

801 - 1630

45

6

2 - 20

11

1

21 - 60

11

2

61 - 200

12

3

201 - 450

23

4

451 - 800

34

5

801 - 1630

45

6

Den

sity

Ground

Air

Water

Add additional chan

nels if req

uired

to accommodate

diversity leve

l and anti-jam

protection.

WNW Network

3

JW

NM

Co

mm

Da

tab

as

e

Co

mm

Da

tab

as

e

1WNW Network Definition

*values in table examples only

Subnet A

OFDM

1425 Ground Members

Sparse

Low Jamming Threat

Desert Terrain

Subnet B

AJ

150 Ground Mem

bers

Dense

Moderate Jamming Threat

Urban Terrain

2Tab

le Lookup

Number of DOCs

Comm

Database Entry

Subnet A = 4 channels

Subnet B = 9 channels

Sp

ec

tru

m

Ma

na

ge

r

Allowab

le

Frequen

cies

JWNM

Processing

5Assign Frequen

cies

Chan

nels to Subnets

Comm

Database Entry

Frequen

cy Chan

nel Definition

4

Reques

t Frequen

cies based

on number

of ch

annels needed and b

andwidths

supported

by each

SiS.

BE

AM

OF

DM

AJ

LP

I/L

PD

0.025

x

0.15

x

0.3

x

0.6

xx

x

1.2

xx

x

3x

xx

5x

xx

10x

xx

20x

x

30x

x

SiS

Ba

nd

wid

th (

Mh

z)

Pla

tfo

rm

Cate

go

ry

Ty

pe

Nu

mb

er

of

No

des

SparseModerate

Dense

2 - 20

11

1

21 - 60

11

2

61 - 200

12

3

201 - 450

23

4

451 - 800

34

5

801 - 1630

45

6

2 - 20

11

1

21 - 60

11

2

61 - 200

12

3

201 - 450

23

4

451 - 800

34

5

801 - 1630

45

6

2 - 20

11

1

21 - 60

11

2

61 - 200

12

3

201 - 450

23

4

451 - 800

34

5

801 - 1630

45

6

Den

sity

Ground

Air

Water

Add additional chan

nels if req

uired

to accommodate

diversity leve

l and anti-jam

protection.

WNW Network

3

•C

urr

en

t sp

ectr

um

man

ag

em

en

t p

rocess

es n

ot

su

ffic

ien

t fo

r d

yn

am

ic,

mu

lti-

wa

vefo

rm e

nvir

on

men

t

9


Sm

art

Rad

io C

ou

ld Im

pro

ve R

esp

on

se D

uri

ng

Co

mp

lex

Pu

blic S

afe

ty E

ven

ts

�M

ult

iag

en

cy s

pectr

um

ass

ign

men

ts &

co

ord

ina

tio

n

�N

etw

ork

co

ntr

ol

an

d m

an

ag

em

en

t

�P

red

efi

ne

d u

ser

co

nfi

gu

rati

on

s

�In

cid

en

t-sp

ec

ific

co

nfi

gu

rati

on

s in

clu

din

g “sc

en

e-

sen

se”

au

tom

ati

c c

on

fig

ura

tio

n

�E

mb

ed

din

g p

oli

cy c

on

sid

era

tio

ns a

t th

e

co

mm

un

icati

on

s d

evic

e le

vel

* L

ist

de

rive

d f

rom

pre

se

nta

tio

n b

y J

oh

n S

. P

ow

ell

, C

ha

ir,

Na

tio

na

l P

ub

lic

Sa

fety

Te

lec

om

mu

nic

ati

on

s C

ou

nc

il (

NP

ST

C)

SD

R W

ork

ing

Gro

up

, a

t C

og

nit

ive

Ra

dio

s

Co

nfe

ren

ce

, L

as

Ve

gas

, N

V,

Ma

r 2004

�F

irst

resp

on

der

eff

ecti

ven

ess r

eq

uir

es im

pro

ved

co

mm

un

icati

on

s

cap

ab

ilit

ies &

in

tero

pera

bilit

y

Pu

bli

c s

afe

ty m

es

h n

etw

ork

ing

be

ne

fits

fro

m s

ma

rt s

pe

ctr

um

acc

ess

Co

gn

itiv

e R

ad

ios c

an

help

ad

dre

ss t

he f

oll

ow

ing

issu

es*:

10


Co

nte

xt-

Aw

are

Rad

ios C

ou

ld Im

pro

ve B

oth

Safe

ty &

Cu

sto

mer

Exp

eri

en

ce

�D

om

ain

aw

are

rad

ios,

avia

tio

n a

nd

passen

ger

sys

tem

s (

Po

rta

ble

Ele

ctr

on

ic D

evic

es

(PE

Ds))

, can

ad

just

beh

avio

r d

uri

ng

a f

lig

ht

en

su

rin

g c

om

plian

ce w

ith

reg

ula

tio

ns

an

d l

imit

ing

in

terf

ere

nce t

o c

riti

cal s

ys

tem

s

Ta

ke

off

La

nd

ing

Air

po

rt

Inte

rna

tio

na

l

Air

sp

ace

Re

gu

lato

ry D

om

ain

“B

”R

eg

ula

tory

Do

ma

in “

A”

In-F

lig

ht

A R

ule

s;

Fu

ll

Se

rvic

e

Facility/Operational DomainRegulatory

Domain

Po

rtab

le E

lec

tro

nic

De

vic

e (

PE

D)

(fu

ture

vers

ion

s o

f cu

rre

nt

sys

tem

s u

nd

er

revie

w

in R

TC

AS

C-2

02

) u

nd

ers

tan

ds

“co

nte

xt”

an

d o

pera

tes a

cco

rdin

g t

o d

om

ain

—

inclu

des m

an

da

tory

overr

ide/s

hu

tdo

wn

to

en

su

re p

rote

cti

on

of

avio

nic

s

OF

FA

Ru

les

;

Lim

ite

d

Se

rvic

e

B R

ule

s;

Lim

ite

d

Se

rvic

e

I R

ule

s;

Lim

ite

d

Se

rvic

e

OF

FB

Ru

les

;

Fu

ll

Se

rvic

e

Air

po

rt

11


Pre

se

nt

Da

y C

om

mu

nit

y A

pp

roa

ch

to

DF

S

Inte

rpre

tati

on

& I

mp

lem

en

tati

on

47 C.F.R.

§§15.403,

15.407

Design Profiles

(technical specs)

Technical Standards Body

FCC

ITU-R

M.1652

802.11(h), (j), . . .

IEEE 802

Motorola

Canopy

Independent Technology Developer

DF

S p

oli

cy/t

ech

nic

al-

sp

ec

s r

eq

uir

ed

4+

years

to

de

velo

p;

Th

is p

ace o

f ru

lem

akin

g i

s a

barr

ier

to r

ap

id in

no

vati

on

in

the C

R a

ren

a.

Issu

e f

or

CR

ap

ps

12


Co

gn

itiv

e R

ad

io C

om

mu

nit

y A

rch

ite

ctu

re(R

IF U

se C

ase)

Regulator A

Regulator B

Policy B1

Published Technical Spec

Design Profiles X(i) X(ii), . . .

Technology Developer

Proprietary Spec.

Policy A1

Technical Standards Body

Industry Consortium

Fo

rmal R

ep

resen

tati

on

s o

f D

esig

n P

rofi

les

Device Type D1 implementations

Device Type D4 implementations

Various RIF

tocognitive radio

device architecture

translators

Profile

{A1, X(i)}

Profile

{B1, Y(i)}

Ult

imate

ly t

hese g

uys s

ho

uld

get

wit

h t

he

pro

gra

m t

oo

!

Device D4

Ontology

Radio

Ontology

Device D1

Ontology

Various RIF

++

tocognitive radio

device architecture

translators

13


Fo

rmal

Rep

resen

tati

on

of

A D

FS

Desig

n P

rofi

le

�S

up

po

se aft

er

sen

sin

g r

ad

ar

all a

cti

vit

y c

an

be t

erm

inate

d

wit

hin

1 s

ec…

�T

hen

ch

eckin

g f

or

rad

ar

every

9 sec s

uff

ices

R1: If

ChannelInUse(?ch,tnow)

LastRadarCheckTime(?ch,?t)

tnow-?t >= 9

Then

Required(radar_check,?ch, tnow)

R2: If

RadarDectected(?ch,?t)

tnow>= ?t

tnow-?t <= 9

ChannelInUse(?ch, tnow)

Then

Required(vacate_signal,?ch, tnow)

–These are deduction rules: statementsabout

what this design requires. They do not cause

a device to perform

the required actions.

–radar_check, vacate_signal are constants.

They denote “abstract”actions

–tnowis a constant denoting the “current

instant of time”

–?ch, ?t are variables over channels and

instants of time.

Th

e s

em

an

tics o

f th

e a

bo

ve (

an

d t

he

pre

dic

ate

s)

are

eit

her

defi

ned

in

an

o

nto

log

y a

nd

/or

by o

ther

axio

ms.

On

tolo

gy+

rule

s f

orm

pre

cis

e r

ep

resen

tati

on

o

f what

is r

eq

uir

ed

, d

oesn

’t s

ay how

to

imp

lem

en

t.

e.g

., u

se D

B f

or

keep

ing

tra

ck o

f ra

dar

ch

eck t

imes?

Ho

w f

ar

back i

n t

ime?

14


Ob

se

rva

tio

ns

�N

o “

imp

ed

an

ce m

ism

atc

h”, in

pri

ncip

le, b

etw

een

ru

les a

nd

o

nto

log

ies a

t th

is level

�R

ule

s a

re s

imp

ly “

axio

ms”

bu

ilt

up

on

th

e d

ed

ucti

ve

backb

on

e o

f w

ell-d

efi

ned

co

ncep

ts in

th

e o

nto

log

y

�S

tan

dard

mo

del-

theo

reti

c s

em

an

tics d

ete

rmin

es w

hat

follo

ws f

rom

wh

at

�N

o in

sta

nce m

an

ag

em

en

t o

r ep

iste

mo

log

icalis

su

es per se

�n

o n

eed

to

co

nsid

er

no

n-m

on

oto

nic

ity,

e.g

., C

WA

�ti

me/t

em

po

ral-

ch

an

ge

vie

wed

sub specie aeternitas

�…

because t

his

is a

specification

of

wh

at

“la

ws”

will

ho

ld t

rue i

f e

very

thin

g w

ork

s a

s i

nte

nd

ed

by t

his

desig

n. T

he w

ho

le p

oin

t is

to

cap

ture

th

ose i

nte

nti

on

s.

15


Imp

lem

en

tati

on

Le

ve

l: R

ule

sto

Guide

De

vic

e B

eh

av

ior

ECA-1:

ON

// this alarm rings every 9 secs

RadarCheckAlarm.isRinging()

IFChannelInUse(?ch)

DO {

result = CheckForRadar(?ch);

if

(result == RADAR_FOUND)

then BroadcastVacateSignal(?ch);

}

–An imperative (ECA) rule: invokes actions,

causesthings to happen.

–Ideally, would like RIF++ based translator to

somehow “translate”R1, R2 into ECA-1

.*

Qu

esti

on

: w

hat

hap

pen

ed

to

tim

e?

Gen

era

l A

nsw

er:

d

iffe

ren

t o

nto

log

y a

t th

is

level. F

or

exam

ple

, n

o s

uch

th

ing

as a

RadarCheckAlarm

at

desig

n level.

Als

o BroadcastVacateSignal in

vo

kes a

p

roced

ure

in

th

e S

DR

im

ple

men

tati

on

: can

no

t exp

ect

co

mp

lete

sem

an

tics f

or

it.

* Our RIF use case does not require this notion of translation: translation within dialectswill

also benefit collaborative development of cognitive radio.

16


Ob

se

rva

tio

ns

�Im

ple

men

tati

on

on

tolo

gie

s d

iffe

ren

t fr

om

desig

n level

�R

ed

ucti

on

of

hig

her

level

theo

reti

cal

no

tio

ns t

o

ob

serv

ati

on

all

y/o

pera

tio

nall

y d

efi

ned

/mea

su

rab

le n

oti

on

s.

�e.g

., a

t h

igh

er

level

no

tio

n o

f radar

invo

lve

s s

om

e r

efe

ren

ce t

o

fun

cti

on

or

pu

rpo

se;

at

de

vic

e l

evel

co

nce

rn i

s h

ow

to

dete

ct

cert

ain

featu

res o

f w

avefo

rms.

�H

ow

mu

ch

hig

her

level

stu

ff t

o p

ut

in d

evic

e l

evel?

(tr

ad

eo

ffs)

�R

ule

s a

t d

evic

e level te

nd

to

be im

pera

tive, e.g

., E

CA

�T

he “

arr

ow

of

tim

e”

is r

eal at

this

level

�S

tan

dard

mo

del-

theo

reti

c s

em

an

tics is n

ot

the w

ho

le s

tory

�In

sta

nce m

an

ag

em

en

t is

su

es

�E

pis

tem

olo

gic

al is

su

es

Key issue in a nutshell: how (and how m

uch) to preserve relationships

among policy & design worldviews and implementation worldview?

17


Co

gn

itiv

e R

ad

io A

rch

ite

ctu

re(T

ran

scen

ds d

esig

n a

nd

im

ple

men

tati

on

levels

)

SDRPerceptions

Actions

Rules

World

Model

Ontologies

Self

Model

Ontology & Rule

Abstraction Layer

Reasoning

Mechanisms

Perception &

Action

Abstraction Layer

Cognitive Radio Application

18


De

vic

e A

rch

ite

ctu

re:

Wo

rld

Mo

de

l &

Se

lf M

od

el

�W

orl

d M

od

el is

th

e “

exte

rnal w

orl

d”

acco

rdin

g t

o t

he C

R

�w

hat

thin

gs a

re p

resen

t, f

acts

ab

ou

t it

s u

ser,

etc

.

�S

elf

Mo

del is

wh

at

the C

R k

no

ws

ab

ou

t it

self

�cu

rren

t g

oals

, cap

ab

ilit

ies (

e.g

., r

ad

ar

sen

sin

g),

etc

.

�M

an

ag

em

en

t o

f w

orl

d &

self

mo

dels

�w

hat

go

es in

, h

ow

it

gets

it,

ho

w lo

ng

it

sta

ys,

an

d h

ow

it

gets

rem

oved

�o

bvio

usly

mu

st

be s

en

sib

le w

ith

resp

ect

to t

he r

ule

s, o

nto

log

y,

an

d r

easo

nin

g m

ech

an

ism

s t

hat

CR

uses

�th

is w

ill b

e d

ete

rmin

ed

to

a g

reat

exte

nt

by t

he u

nd

erl

yin

g S

DR

an

d t

he P

AA

L l

aye

r

19


De

vic

e A

rch

ite

ctu

re f

or

En

ha

nc

ed

DF

S S

erv

ice

User

User

Agent

Policy

Checker

DFS

Application

Cognitive Radio

ok t

o u

se

ch

an

nel C

?N

o. B

locked

by

rad

ar!

If the goal of using channel C is blocked by the presence of radar-signal r with heading h1

and s is a control-signal with heading h2 received from Master m implying channelC availability

and h2 and h1 are sufficiently distinct

Th

en

Attempt to m

ove in the direction indicated by h2 until the signal strength of r is below the required threshold

and then attempt to associate with m

receiv

ed

wh

en

? a

ny c

on

trary

in

fo r

eceiv

ed

aft

er?

Wo

rld

& S

elf

Mo

del m

an

ag

em

en

t g

uara

nte

es t

imelin

ess.

20


Th

ou

gh

ts…

�W

hen

th

inkin

g a

bo

ut

on

tolo

gy+

rule

in

tera

cti

on

�D

iffe

ren

t le

vels

en

tail

dif

fere

nt

co

nsid

era

tio

ns

�C

om

mu

nit

y a

rch

itectu

re (

po

lic

y)

& d

esig

n p

rofi

le l

evels

-T

hin

k in

sub specie aeternitas

mo

de:

rule

s+

on

tolo

gy t

og

eth

er

descri

be

wh

at is

.

-H

ow

to

make it

po

ssib

le t

o r

easo

n about

po

lic

y &

desig

n p

rofi

les

�Im

ple

men

tati

on

le

vel

-D

esig

nin

g s

om

eth

ing

wh

ose b

eh

avio

r is

gu

ided

(in

a c

au

sal sen

se)

by

po

lic

y

-G

uara

nte

es n

eed

fo

r ru

les w

ith

im

pera

tive s

em

an

tics

-B

e c

lear

ab

ou

t th

e s

tru

ctu

re o

f self

an

d w

orl

d m

od

els

an

d h

ow

man

ag

ed

:

this

will h

elp

to

fig

ure

ou

t h

ow

ru

les s

ho

uld

be w

ritt

en

.

�R

ela

tio

ns a

mo

ng

on

tolo

gie

s a

t d

iffe

ren

t le

vels

fu

nd

am

en

tal

to “

real”

un

ders

tan

din

g

�n

ot

necessari

ly n

eed

ed

in

ap

p.

�b

ut

essen

tial

to R

IF+

+!!

!

21


Clo

sin

g R

em

ark

s

�T

he

reg

ula

tory

co

mm

un

ity, te

ch

sta

nd

ard

s o

rgs, an

dth

e

tech

no

log

y d

evelo

pers

mu

st

have s

om

e s

hare

d

un

ders

tan

din

g o

f h

ow

to

fo

rmall

y s

pecif

y C

R b

eh

avio

rs;

�A

Co

gn

itiv

e R

ad

io C

om

mu

nit

y A

rch

itectu

re b

ased

on

sem

an

tic t

ech

no

log

ies o

ffers

a f

ram

ew

ork

fo

r d

evelo

pin

g

this

sh

are

d u

nd

ers

tan

din

g;

�T

his

req

uir

es k

no

wed

ge r

ep

resen

tati

on

in

th

e f

orm

of

bo

th

on

tolo

gie

s a

nd

ru

les;

�R

IF o

ffers

th

e m

ean

s t

o d

eco

up

le t

he c

om

mu

nit

y’s

u

nd

ers

tan

din

g o

f th

e r

ule

s f

rom

sp

ecif

ic r

ule

-based

in

fere

nce e

ng

ines;

experiments in cognitive radio and dynamic spectrum access ... · experiments in cognitive radio...

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