ECE544MobileNetworks2015.pptx

8/18/2019 ECE544MobileNetworks2015.pptx

1/79

Overview of MobileNetworking

ECE 544 2015Prof. D. Rayc a!" !ri

#li"e$ co!rte$y of Dr. #a% Nel$on


2/79

Mobile& 'irele$$ Device$• (oal$

– )llowco%%!nication to

an" fro% t e*nternet to %obile"evice$

– )llow %obile

"evice$ in t e $a%earea to talk without going t ro!ginfra$tr!ct!re

Mobile wirelesscommunication devices arebecoming ubiquitous

#%art + one$

E%ergencyre$+on$e

,e ic!lartec nology


3/79

' y #t!"y MobileNetworking-

• WapReview : e totaln!%ber of %obile*nternet !$er$/ 1.05billion& w ic in 200 for

t e r$t ti%e $!r+a$$e"t e total n!%ber of PC'eb !$er$ 1 billion3

• DigitalStats : (June2009 *n t e la$t $i%ont $& !+loa"$ fro%%obile + one$ to

o! !be 6!%+ by 17008.

• DigitalStats : ' en+o$e" wit t e 9!e$tion:' ic "o yo! acce$$#ocial Network $ite$

fro% %ore& %obile + oneor co%+!ter-;

#a%+le $i21& ?a+ane$e $!rvey3

– Co%+!ter 14.08 – Mobile + one 70.48 – @ot abo!t t e $a%e

15.08 – DonAt know 0.B8


4/79


5/79

Protocol #tack

P y$ical

ink

Network

ran$+ort

)++lication

'irele$$ +ro+agation i$$!e$

*nterference Fi""en ter%inal

E$tabli$ ing ro!te$ a""re$$ing

Reliable& in or"er "elivery conge$tion control

#en$ing e%ergency re$+on$e& $ocial networking

ayer Mobility C allenge$


6/79

Mobile Networking o+ic$/ect!re O!tline

Mobile Client$ on t e *nternet

Mobile )" oc Network$M)NE $3

Delay olerant Network$D N$3

Co%%!nicate to fro%*nternet

*nfra$tr!ct!re in 1 o+ )""re$$ing Proble%$

Co%%!nicate wit innetwork

No infra$tr!ct!re Relatively igconnectivity

Co%%!nicate wit innetwork

No infra$tr!ct!re ow connectivity


7/79

Mobile Client$ on t e *nternetal$o $ee $!++le%entary Mobile *Pt!torial $li"e$ fro% E!re$co%3


8/79

Mobile Fo$t on t e *nternet• (oal/ Maintain two way connectivity

to *nternet an" a %obile o$t.

Net ) Net @

*nternet

*PG)

Hor

*PG)


9/79

*P )""re$$e$• ' at "o *P a""re$$e$ really %ean-

21>. B. >.11B

Network Fo$t

*P a""re$$ i$ forrouting +!r+o$e$

Fence& t ey%!$t c ange

w en a no"ec ange$network$

*P a""re$$e$ are topologically dependent an"ence are ba" c oice$ for long la$ting na%e$ in

%obile environ%ent$


10/79

Mobile Fo$t on t e *nternet

•

#ol!tion$- – C ange *P a""re$$ Connectivity i$ lo$tI w at i$

o$tA$ *P- – Jee+ *P a""re$$ Ro!ting will fail... o$t not fo!n".

Fow can # $en" to t e %ove" %obileo$t-

Net ) Net @

*nternet

*PG) *PG@

Hor*PG)


11/79

Mobile *P #ol!tion• Mobile o$t keeps itA$ ol" *P a""re$$& an" get$

$o%eone to forwar" %e$$age$ to it• *t %!$t infor% t i$ K$o%eone; of itA$ new

a""re$$• )gent$ to el+ L home agent an" foreign agent

Ol" *P

New *P

Referre" to a$ K o%e a""re$$;

Referre" to a$ Kcare of a""re$$;


12/79

Mobile *P #ol!tion

FN

R1 R>

HN HNR2

F)

MF

MFCF

H)

Mobile Fo$t/a o$t or ro!ter ca+ableof c anging it$ +oint of attac %ent to t e *nternet

Horeign Network/a network& ot er t an M)A$ o%enetwork& t at MF i$ c!rrently attac e"to.

Corre$+on"ing Fo$t/a o$t or ro!ter co%%!nicationgwit a %obile no"e.

Fo%e Network/t e network i"enti e"wit a %obile no"e

Fo%e )""re$$/MFA$ +er%anent *P a""re$$& network *D oft i$ a""re$$ i"enti e$ t e %obileA$ o%enetwork.

Fo%e )gent/a ro!ter attac e" to t e MFA$ o%e network%aintain$ c!rrent location infor%ation for t e MFi$ re$+on$ible for forwar"ing +acket$ "e$tine" for tMF w en MF i$ away fro% o%e.

Horeign )gent H)3a ro!ter in t e foreign network t at t e MF i$ vi$iting +rovi"e$ro!ting $ervice$ to t e MF %ay $erve a$ "efa!lt ro!ter foro!tgoing +acket fro% MF

Ro!te O+ti%i


13/79

Ro!te O+ti%i


14/79

Mobile )" oc Network$


15/79


16/79

)" oc Network$

• (oal/ No"e$ wit in t e network can $en" "ata betweent e%$elve$.

• C allenge$/ – No centrali


17/79

)" oc Network$

• No"e$ t at want to ro!te %e$$age$ %!$t/ – Hin" o!t abo!t t e to+ology of t e network – $e t at to+ology to "o $o%et ing wit t e

%e$$age

Control Plane

Data Plane

S

D


18/79

Ro!ting Protocol Categorie$• Proactive/

– No"e$ actively %aintain an" $ are to+ologyinfor%ation& regar"le$$ of if t ere i$ "ata to

$en" – (enerally ti%er or event ba$e"

• Reactive On "e%an"3/ – K a


19/79

Ro!ting Protocol Categorie$

• ocal ne t o+ forwar"ing/ – Con$!lt forwar"ing table for a ne t o+ – Co%+letely local "eci$ion

• #o!rce ro!ting/ – #o!rce no"e +lace$ co%+lete +at in

+acket ea"er – *nter%e"iate no"e$ "onAt ave to

con$!lt t eir forwar"ing table$

Data Plane

# ) @ D

) @D


20/79

Reactive Protocol$• Na%e$ are !$ef!l int$ at

!n"er$tan"ing t e +rotocol+ro+ertie$/

)" oc On "e%an" Di$tance ,ector)OD,3

Dyna%ic #o!rce Ro!ting D#R3

#o!rceRo!ting

Ne t o+Horwar"ing

Di$tance,ector

ReactiveM)NE

M)NE


21/79

21

Dyna%ic #o!rce Ro!ting D#R3Hro% # weta ?ainA$ #li"e$

• ' en no"e # want$ to $en" a +acketto no"e D& b!t "oe$ not know a ro!teto D& no"e # initiate$ a ro!te"i$covery.

• #o!rce no"e # oo"$ t e networkwit ro!te re9!e$t RREQ3 +acket$

al$o calle" 9!ery +acket$3.• Eac no"e a++en"$ it$ own a""re$$

in t e +acket ea"er w en

forwar"ing RREQ.


22/79

22

Ro!te Di$covery in D#R

)

# E

H

@

C

( D

RREQ broa"ca$t#S

re+re$ent$ a no"e t at a$ receive" RREQ for D fro% #.

T&..&..S Re+re$ent$ li$t of a""re$$e$ a++en"e" to RREQ.

) no"e receiving a RREQ rebroa"ca$t$ it e actly once.


23/79

23


re+re$ent$ a no"e t at a$ receive" RREQ for D fro% #.

)

# E

H

@

C

( D

RREQ broa"ca$t#&ES

T&..&..S Re+re$ent$ li$t of a""re$$e$ a++en"e" to RREQ.

#&CS

#&)S

) no"e receiving a RREQ rebroa"ca$t$ it e actly once.


24/79

24


)

# E

H

@

C

( D

RREQ broa"ca$t

#&E&HS

#&C&(S

#&)&@S

De$tination D receive$ RREQ via ( an" H.

*t "oe$ not broa"ca$t it f!rt er.


25/79

25


• De$tination D on receiving t e r$tRREQ& $en"$ a Ro!te Re+ly RREP3.

• RREP i$ $ent on a ro!te obtaine" byrever$ing t e ro!te a++en"e" toreceive" RREQ.

• RREP incl!"e$ t e rever$e ro!te fro%# to D on w ic RREQ wa$ receive"by no"e D.


26/79

26

Ro!te Re+ly in D#R

)

# E

H

@

C

( D

RREP nica$t

D&H&ES

Rever$e ro!tein t e ea"erof RREP


27/79

27

Ro!te Cac ing in D#R• No"e # on receiving RREP& Kcac e$;

t e ro!te incl!"e" in t e RREP.• ' en no"e # $en"$ a "ata +acket to

D& t e entire ro!te i$ incl!"e" in t e+acket ea"er

– Fence t e na%e $o!rce ro!ting .• *nter%e"iate no"e$ !$e t e $o!rce

ro!te incl!"e" in a +acket to"eter%ine to w o% a +acket $ o!l"

be forwar"e".


28/79

28

Data Delivery in D#R

)

# E

H

@

C

( D

Cac e on #/#&E&H&DS

D) ) #&E&H&DS

D) ) +acket nica$t

#o!rce ro!te $i


29/79

29

Dyna%ic #o!rce Ro!ting/)"vantage$

• Source routing: no $+ecial %ec ani$% nee"e"to eli%inate loo+$.

• !n demand routing: Ro!te$ %aintaine" onlybetween no"e$ w o nee" to co%%!nicate

– Re"!ce$ over ea" of ro!te %aintenance.• Route cac"ing can f!rt er re"!ce ro!te

"i$covery over ea".• ) $ingle ro!te "i$covery %ay yiel" %any ro!te$

to t e "e$tination& "!e to inter%e"iate no"e$re+lying fro% local cac e$.

– $ef!l w en ro!te break$.


30/79

30

Dyna%ic #o!rce Ro!ting/ Di$a"vantage$

•

#ot scalable: Packet ea"er $i


31/79

31

Dyna%ic #o!rce Ro!ting/Di$a"vantage$

• Stale cac"e problem : )n inter%e"iateno"e %ay $en" Ro!te Re+ly !$ing a $talecac e" ro!te& t !$ +oll!ting ot er cac e$.

•

i$ +roble% can be ea$e" if $o%e%ec ani$% to +!rge +otentially3 invali"cac e" ro!te$ i$ incor+orate".

• C!rrent re$earc / ow to invali"ate cac e$e ectively.

– E a%+le/ i%er ba$e". Or +ro+agate t e ro!teerror wi"ely.


32/79

32

)" Foc On De%an" Di$tance,ector Ro!ting )OD,3

Hro% # weta ?ainA$ #li"e$• )OD, retain$ t e "e$irable feat!re of D#R t at

ro!te$ are %aintaine" only between no"e$w ic nee" to co%%!nicate.

•

)OD, atte%+t$ to i%+rove on D#R by%aintaining ro!ting table$ at t e no"e$& $ot at "ata +acket$ "o not ave to containro!te$.

•

No cac e$ are !$e". – Only one ro!te +er "e$tination in t e ro!ting table. – Only %aintain t e fre$ e$t ro!te& if %!lti+le

+o$$ibilitie$.


33/79

33

)OD,•

Ro!te Re9!e$t$ RREQ3 are forwar"e" ina %anner $i%ilar to D#R.• ' en a no"e re broa"ca$t$ a RREQ& it

$et$ !+ a rever$e +at +ointing towar"$

t e $o!rce. – i$ i$ $o t at t e RREP can get back to t e

$o!rce.• ' en t e inten"e" "e$tination receive$

a RREQ& it re+lie$ by $en"ing a RREP.• RREP travel$ along t e rever$e +at $et

!+ w en RREQ i$ forwar"e".


34/79

34

)OD, Ro!te Di$covery

• #o!rce oo"$ ro!te re9!e$t RREQ3 in t e network.• Rever$e +at $ are for%e" w en a no"e ear$ a ro!te

re9!e$t.• Eac no"e forwar"$ t e re9!e$t only once +!re oo"ing3.

)

# E

H

@

C

( D

RREQ broa"ca$t


35/79

35


)

# E

H

@

C

( D

• #o!rce oo"$ ro!te re9!e$t in t e network.• Rever$e +at $ are for%e" w en a no"e ear$ a ro!te


Rever$e Pat


36/79

36


)

# E

H

@

C

( D

• $e$ o+ by o+ ro!ting.• Rever$e +at $ are for%e" w en a no"e ear$ a ro!te


RREQ broa"ca$t

Rever$e Pat


37/79

37


)

# E

H

@

C

( D

• $e$ o+ by o+ ro!ting.• Rever$e +at $ are for%e" w en a no"e ear$ a ro!te


Rever$e Pat


38/79

38


•

Ro!te re+ly RREP3 i$ forwar"e" viat e rever$e +at .

)

# E

H

@

C

( D

Rever$e Pat


39/79

39


• Ro!te re+ly i$ forwar"e" via t e rever$e+at I t !$ for%ing t e forwar" +at .

• e forwar" +at i$ !$e" to ro!te "ata+acket$.

)

# E

H

@

C

( D

Horwar" Pat

Rever$e Pat


40/79

40

Ro!te E +iry on i%eo!t• ) ro!ting table entry %aintaining a

rever$e +at i$ invali"ate" after a ti%eo!tinterval

–

i%eo!t $ o!l" be long eno!g to allow RREPto co%e back• ) ro!ting table entry %aintaining a

forwar" +at i$ al$o invali"ate" if !n!$e"for certain interval.

– i$ %ean$ !n!$e" ro!te$ are +!rge". – Note t at t e ro!te %ay $till be vali".


41/79

41

Ro!te E +iry

• n!$e" rever$e +at $ e +ire ba$e"on a ti%er.

)

# E

H

@

C

( D

Horwar" Pat


42/79

42

Po$$ibility of Ro!ting oo+$U• $ef!l o+ti%i


43/79

43

Po$$ibility of Ro!ting oo+$U

• )$$!%e t at ) "oe$ not know abo!t fail!re of linkC D beca!$e ro!te error $ent by C i$ lo$t .

• Now C +erfor%$ a ro!te "i$covery for D. No"e )receive$ t e ro!te re9!e$t $ay& via +at C E )3

• No"e ) will re+ly $ince ) know$ a ro!te to D viano"e @

• Results in a loop ()or instance* '%+%,%-%'

) @ C D

E


44/79

44

$e of #e9!ence N!%ber$ in)OD,

•

Eac no"e T %aintain$ a $e9!encen!%ber an" incre%ent$ it at $!itableinterval$.

• #e9. no. act$ like a logical clock.• Eac no"e wit a ro!te to T in t e

ro!ting table& al$o %aintain$ a "e$tination$e9!ence n!%ber for T& w ic i$ A$ latestknowledge of TA$ $e9!ence n!%ber.

• De$tination $e9!ence no. can be !$e" toor"er ro!ting !+"ate$.


45/79

45

$e of #e9!ence N!%ber$ in)OD,

• oo+ free"o%/ e +rotocol %aintain$ t e invariant t at t e"e$tination $e9!ence n!%ber for any "e$tination D never"ecrea$e$ along any vali" ro!te.

– No ro!ting info i$ acce+te" by a no"e T fro% any no"e & w ere A$"e$tination $e9. no. for D i$ le$$ t an TA$ "e$tination $e9. no. for D.

• Hre$ e$t ro!te/ (iven a c oice of %!lti+le ro!te$& t e+rotocol alway$ c oo$e$ t e one wit t e ig e$t $e9!encen!%ber.

T D-

De$t $e9 no. = 10 De$t $e9 no. = 7

Nee"$ a ro!teto D

Fa$ a ro!te to D

#e9. no. = 15

RREQ carrie$ 10

"oe$ not re+ly& b!tforwar"$ t e RREQ


46/79

46

Fow $ing #e9!ence N!%ber$ can)voi" oo+-

• ink fail!re incre%ent$ t e "e$tination $e9. no.at C now i$ 103.

•

*f C nee"$ a ro!te to D& RREQ carrie$ t e c!rrent"e$t. $e9. no. 103.• ) "oe$ not re+ly a$ it$ own "e$t. $e9. no. i$ le$$

t an 10.

) @ C D

E

10V

V

7

5 )ll $e9 noA$ are for D

calle" "e$tination $e9.no.3


47/79

47

#!%%ary/ )OD,• No $o!rce ro!ting. @a$e" on ro!ting table$.• $e of $e9!ence n!%ber$ to +revent loo+$.• )t %o$t one ro!te +er "e$tination

%aintaine" at eac no"e – Only t e fre$ e$t one i$ %aintaine" via

"e$tination $e9. no.3 – #tale ro!te +roble% i$ le$$ $evere. – )fter link break& all ro!te$ !$ing t e faile" link

are era$e".• n!$e" ro!te$ e +ire even if vali".


48/79

Proactive Protocol$

O+ti%i


49/79

49

ink #tate Ro!ting•

Eac no"e oo"$ t e network wit t e $tat!$ of it$link$ – Hloo" can be +erio"ic. – Or& w en a neig bor oo" c ange i$ "etecte".

• Eac no"e kee+$ track of link $tate infor%ationreceive" fro% ot er no"e$

– !$ b!il"$ it$ own view of t e network connectivity.• Eac no"e !$e$ it$ view of network connectivity to

con$tr!ct a ro!ting table for eac "e$tination. – Hor e a%+le& eac no"e can r!n a $ orte$t +at

algorit % e.g.& Di6k$traA$3 on it$ own view of t econnectivity gra+ .

– Di erent no"e$ can !$e "i erent ob6ective for ro!ting.


50/79

y+e$ of Di$covery• Di$cover yo!r local neighbors

– Fello %e$$age$ – #ent only 1 o+& never oo"e"

• Di$cover t e total network to+ology – ink $tate a"verti$e%ent #)3

%e$$age$ – Hloo"e" t ro!g o!t t e network


51/79

ink #tate )lgorit %

Flooding:1) Periodically distribute link-stateadvertisement (LSA) to neighbors

- LSA contains delays to each

neighbor2) nstall received LSA in LS database!) "e-distribute LSA to all neighbors

Path #om$utation1) %se &i'kstra s shortest $ath algorithmto com$ute distances to all destinations2) nstall destination* ne+tho$, $air in

or.arding table


52/79

52

O #R/ O+ti%i


53/79

53

ra"itional Hloo"ing

24 retran$%i$$ion$nee"e" to oo"t e network


54/79

54

M!lti+oint Relay$

11 retran$%i$$ion$nee"e" to oo"t e network


55/79

55

O+ti%i


56/79

Delay olerant Network$

Di$ !+ti l t


57/79

Di$r!+tion olerantNetwork$

• D N C aracteri$tic$ – *nter%ittent connectivity – Partitioning –

No g!arantee of en" to en" +at $• (oal$/

– Fig %e$$age "elivery ratio – )cce+table "elay

• Ro!ting )++roac – #tore carry an" forwar" ro!ting – Re+lication

57

+mergenc responsenetwor$s

'ommunit networ$s-attle.eld networ$s

N R li


58/79

No Reliance on*nfra$tr!ct!re

• @ene t of D N co%%!nication – )llow$ en" !$er$ to not rely on

infra$tr!ct!re• *nfra$tr!ct!re %ay be not

available –

De$troye" e%ergency re$+on$e3 – Never t ere %ilitary t ir" worl""evelo+%ent3

• *nfra$tr!ct!re %ay not be i"eal – Co$tly co%%!nity network$3 – Overloa"e" #low co%%!nity

network$3

5

*n$tea"& %obility i$ !$e" tofor% connection$

Re+lication i$ !$e" to

overco%e inter%ittentconnectivity


59/79

Ro!ting Con$i"eration$• )re contact$ $c e"!le" or not-• Can * e tract any infor%ation fro%

t e %obility-• @a$e" on t e$e 9!e$tion$/

– Fow %!c "o * re+licate- – ' o "o * give re+lica$ to- – ' ic +acket$ "o * $en" "ro+ r$t-


60/79

Ro!ting Categorie$

Re+lication #cale

DirectDelivery Q!ota ba$e"

Hloo"ingba$e" E+i"e%ic

#+ray an" 'ait

#+ray an" Hoc!$Enco!nter ba$e" Ro!ting

Ma Pro+

Pro+ etR)P*D

Far" li%it onn!%ber ofre+licate$ +er%e$$age

No li%it on n!%berof re+lica$


61/79

E+i"e%ic Ro!ting• *f not ing i$ known an" re$o!rce$ are

available& 6!$t $en" to everyoneU• E+i"e%ic ro!ting i$ t e D N

e9!ivalent to oo"ing/

#

D

*

#

D

*

#

D

*


62/79

#ync roni


63/79

Pro$ an" Con$• Pro$/

– E tre%ely $i%+le to i%+le%ent – O+ti%al in ter%$ of "elivery an" "elay i)

no resource constraints• Con$/

– Perfor%ance greatly $! er$ if t ere are

re$o!rce con$traint$ b! er& ban"wi"t &contact "!ration3


64/79

Ma Pro+• Fig re+lication i$ goo"& if we can

+ro+erly %anage t e b! er$ – ' ic %e$$age$ "o * $en" r$t- – ' ic %e$$age$ "o * "ro+ r$t-

• #till re+licate all %e$$age$ to allcontact$U


65/79

Ma Pro+

S D1. @an"wi"t

2. #torage>. Contact "!ration

• Maintain a +riority or"ere" 9!e!e – Priority i$ estimated delivery likelihood – Horwar" co+ie$ of all %e$$age$ in t i$

or"er

W"ic" pac$ets do /send .rst


66/79

Meeting Probabilitie$• Eac no"e %aintain$ a vector of $i


67/79

Pat Co$t Calc!lation• e co$t of a +at i$

t e $!% of+robabilitie$ t at eacconnection on t e

+at "oe$ not occ!r• C oo$e t e +at wit

%ini%al co$t

,

D

'-

@ C

.5 .5

@ C.B .4

) C

.25 .5

D

.25

) @.2 .B

D.2

at" 'osts:)@D = 1 .53 W 1 .253 = 1.25)CD = 1 .53 W 1 .23 = 1.>)@CD = 1 .53 W 1 .53 W 1 .23 = 1.)C@D = 1 .53 W 1 .B3 W 1 .253 = 1.B5

Co%+le%entary


68/79

Co%+le%entaryMec ani$%$

• )cknowle"ge%ent$ – Hloo"e"& to clear o!t

b! er$ – Fa$ of %e$$age

12 bit$3• Packet K ea" $tart;

– (ive +riority to low o+co!nt +acket$

• @! er %anage%ent – Dro+ or"er

• )cknowle"ge"%e$$age$

• owe$t "elivery $core• Fig e$t o+ co!nt

rotocol1. Direct "elivery

2. Ro!tinginfor%ation>. )cknowle"ge%ent

$4. ow o+ co!nt

+kt$5. Re%aining +kt$


69/79

#+ray an" 'ait

• #trictly li%it re+lication – Me$$age co+ie$ contain quota – Di$trib!te 9!ota at re+lication

ti%e• @ene t$

– Re$o!rce frien"ly• i%itation$

– Potential re"!ce" "eliveryratio

– May %i$$ i%+ortant contacto++ort!nitie$

BV

4

2 2

Me$$age

Q!ota

1 1

@! er %anage%ent i$ too "iXc!lt& $oin$tea" 6!$t li%it re+lication


70/79

E a%+le

#

D

4

1 2

Spra "ase(ive a re+lica wit alf%y 9!ota to %yc!rrent contact

#

D

1

1 1

Wait "ase' en 9!ota i$ 1 for are+lica& only "irect"elivery i$ allowe"

1 1


71/79


– ,ery re$o!rce frien"ly – Doe$nAt re9!ire a co%+le b! er

%anage%ent tec ni9!e – No ro!ting over ea"• Con$/

– o! %ay give val!able 9!ota away to!$ele$$ no"e$

– No"e %i ing %!$t be ig an"& to $o%ee ten"& ran"o%


72/79

Enco!nter @a$e" Ro!ting• *n$ig t/

– Popularity can be !$e" to "eter%ine forwar"ing !$ef!lne$$• Naive )++roac

– (ive entire %e$$age& or a re+lica of t e %e$$age& to t e %ore+o+!lar no"e

• E@RA$ )++roac – Di$trib!te 9!ota in proportion to no"e K+o+!larity; – Ea$ily e ten"able to groups by "i$trib!ting 9!ota in +ro+ortion

to group +o+!larity

ittle ot

72

ow+o+!larity

Fig+o+!larity


73/79

Mea$!ring Po+!larity• Encounter value E,3

– (a!ge overall +o+!larity of a no"e – Co!nting 'in"ow

• Co!nt contact$ +er a+$ not !ni9!e3 wit in a $+eci e"

window C'C3• +"ate !$ing an e +onentially weig te" %oving average

7>

•

E, can be e +an"e" to %!lti+le "i%en$ion$ – (a!ge +o+!larity wit "i erent gro!+$ – Eac "i%en$ion re+re$ent$ a gro!+ – +"ate E, in t e "i%en$ion of t e contactA$

gro!+ $3

EV CWC EV ⋅−+⋅← )1( α α


74/79

Di$trib!ting Q!ota• No"e ) %eet$ No"e @

– (et No"e @A$ E, e tre%ely low over ea"3 – Deter%ine a%o!nt of initial 9!ota M if any3 to kee+

an" to give No"e @& for eac %e$$age in A’s b! er

– ran$%it a co+y of message wit t e new 9!ota for @• Pro+ortional

– Q!ota ow fro% ig +o+!larity to low +o+!larity canocc!r& %itigating local %a i%!%$

74

+=

B A

B

EV EV

EV M Give


75/79

E a%+le

75

, -

4

E, ) = 5 E, @ = 15


76/79

E a%+le

7B

) $en"$ Y of all 9!ota to@

@ $en"$ Z of all 9!ota to)

, -

4

E, ) = 5 E, @ = 15

4

3

155

15=

+=

+ B A

B

EV EV

EV

4

1

155

5=

+=

+ B A

A

EV EV

EV


77/79

E a%+le

77

) $en"$ Y of all 9!ota to@

@ $en"$ Z of all 9!ota to)

, -

4

E, ) = 5 E, @ = 151

>

B

2

(ive away

(ive away

Jee+

Jee+

4

3

155

15=

+=

+ B A

B

EV EV

EV

4

1

155

5=

+=

+ B A

A

EV EV

EV


78/79


– ,ery re$o!rce frien"ly – ,ery low ro!ting over ea" – Can $till ac ieve ig re$!lt$

• Con$/ – )$$!%e$ !neven +o+!laritie$& an" t at

+o+!larity will $tay t e $a%e for a no"e – Can %i$$ i%+ortant contact

o++ort!nitie$ "!e to being 9!ota ba$e"


79/79

Concl!$ion$• Mobile networking i$ a very

intere$ting an" active el" ofre$earc U

– D N$ – ,e ic!lar network$ – n"erwater network$ –

#en$or network$• Ot er to+ic$& $!c a$ %obile $ec!rity

an" +rivacy& ave lot$ of activity a$

Date post:	07-Jul-2018
Category:	Documents
Upload:	nikunj-shah
View:	213 times
Download:	0 times

ECE544MobileNetworks2015.pptx

Documents