airmagnet design

8/2/2019 Airmagnet Design

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A Tchy Whitpapr

Bst Practics

r Wirss Sit Dsi



A Tchy Whitpapr

TABle of ConTenTS

Ar Sit Survys Ray Rquird?

AirMat Apprach t Wirss Sit Dsi 1

Phas I: Prparati Phas 1

Phas II: Pai Phas 2

Phas III: Survyi Phas 3

Prrmi Activ ad Passiv Survys 4

Maai Itrrc 5

AirMat eabs Usrs T Maa Itrrc i Svra Ways 6

Pipiti Rami Aras 7

estabishi optima QS fr A ed Usrs 8

D I nd Accss Pits o each fr? 9

estabishi Strict Scurity 10

Pai outdr ntwrks 10

Phas IV: Rprti ad Si- Phas 11

Phas V: Pridic Survys 12

Ccusi 13

Abut AirMat 13

Ctact Us 13

i | AirMat, Ic. • Bst Practics r Wirss Sit Dsi



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Sit Survys ar dd t sur th succssu ad

efcient deployment of wireless networks. To understand

the need for a survey, you should rst understand the

basic a a wirss twrk, which is t prvidapprpriat cvra ad thruhput t a d usrs

whi kpi itrrc t a miimum.

Rf sias ar vry uprdictab. I a accss pit is

pacd i a p virmt with bstacs, th

sias usuay maitai a mi-dirctia pattr.

Hwvr, wh bstacs ad was with dirt

charactristics ar itrducd, th Rf sias ar

disruptd ad accss pit cvra wi vary basd

cati.

Sit Survys dtrmi th sia cvra, thruhput

rquirmts, itrri surcs, dad spts, pttia

rami bhavir, tc ad this hps dtrmi (1) what

wirss quipmt t purchas, i.. hw may accss

pits t buy (2) whr t dpy accss pits, ad (3)

how to congure each access point for optimal coverage

r a d usrs. It ca asiy b said that withut sit

surveys; it would be difcult to determine the capital

ivstmt dd t dpy th wirss twrk i a

timely and efcient manner.

It is imprtat t t raiz vry wirss dpymt

in terms of requirements; for example, an ofce

virmt with y data cits usi th wirss

twrk r Itrt accss may trat a w dad spts,

but this is ubarab i a hspita virmt whr th

dctrs/urss rquir accss t th twrk t t ra-

tim patit irmati. Withut sit survys it wud b

virtuay impssib t dtrmi i th rquirmts

ach d usr ar bi mt.

Sit Survys ar rquird r:• nw istaatis: T btai th umbr

accss pits rquird ad catis basd prdictiv

prrmac aaysis.

• existi istaatis: T vriy th umbr accss

pits rquird vrsus th umbr actuay dpyd ad

vaidat thir cati t sur ptima prrmac r

a d usrs.

AIRMAgneT’S APPRoACH To

WIReleSS SITe DeSIgn

Sit survys ar usd t pa ad dpy a w wirss

network, as well as recongure or verify the performance of

a xisti twrk. This dcumt utis AirMat’s

mthdy r bth ths sit survyi scaris.

This mthdy is a rsut AirMat’s csutati

with its w custmrs, ad isiht it th bst practics

irastructur vdrs ad thr idustry adrs.

Phas I: Prparati Phas

Br purchasi ay twrki quipmt r

dpyi a cmpty w wirss tchy, usrs

shud btai aswrs t th wi qustis:

• Hw may usrs rquir wirss srvic ad

what appicatis wi thy us? Wi thy d

a rami aciity?

Ar Sit Survys

Ray Rquird?

AirMat, Ic. • Bst Practics r Wirss Sit Dsi | 1



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2 | AirMat, Ic. • Bst Practics r Wirss Sit Dsi

• Is wirss accss dd r idrs r

utdrs r bth?

• Ar thr ay kw majr itrri surcs

such as radar istaatis r catria

catis?

• What ar th scurity picis ad rquirmts r

wirss twrks?

• Are any building/oor blueprints available?

Phas II: Pai Phas

Whr d I start th wirss dpymt? What quipmt

d I purchas? By kwi th pai capabiity, usrs

can signicantly reduce the time and effort needed

t dpy a wirss twrk. Th Air Mat Par

prvids quick visibiity it ths rquirmts, such

as:

• estimatd umbr accss pits dd ad

thir sia cvra

• estimatd cati th accss pits

• estimatd itrrc ccurri btw th

dpyd accss pits

• Rf aka t utsid th crprat physica

budaris

• Data spd vaus r th pad Accss Pits

I th pai phas it is critica t udrstad th

cts varius buidi matrias ad bstacs thprrmac th twrk. obstructis btw th

AP ad statis ca ad t diracti, rracti, ad

reection of the RF signal and degrade the signal quality

r v ad t Rf spia utsid th crprat physica

budary. giv th ct that mtas ca hav sia

quaity, it is imprtat t t th cati st ad

thr mta matrias i th sit irastructur. AirMat

Par assists usrs i ths aras by prvidi a

prdictiv map th buidi’s Rf virmt.

Prdictiv Mappi Aids Sit Dsi

AirMat Par abs usrs t ad a map

the building or oor, and customize the space using

a ibrary was, widws, drs, tc. Dirt wa

charactristics (ccrt was, brick was, ass/mta

drs ad widws) ad itrrc aras (cubics,

vatr shats, warhus with w/mdium/hih stck)

ar markd. Accss pits with th dsird cha,trasmittd pwr, ata ad mdia-typ ca th b

placed manually on the site oor plan at places where they

ar xpctd. Th prdictd map th Rf virmt

is th simuatd, abi usrs t twak AP catis

and other congurations until optimal coverage is

achivd r a usrs. Usrs urthr hav th pti

addi, rmvi r mvi APs t dirt catis,

ad th prati cha r th trasmittd pwr

ca b chad t prvt cvra hs, miimiz

itrrc ad v rduc scurity risks by prvti

Rf spia utsid th crprat physica budary. As th AirMat “Par Advisr” ca b mpyd

fiur 1: AirMat Par dispayi pttia cvra hs/dad

spts i th wirss twrk

Dead spots

(minimum

required:

-55 dBm)



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fiur 2: Additi th 5th accss pit pus cvra hs

Simulating an

additional AP

solves the

problem

Rprti Prvids Dpymt/Purchasi

Buprit

Reporting greatly simplies the deployment phase.

Atr usrs hav simuatd thir twrk r ptima

prrmac, thy ca rat a cmprhsiv rprt

that includes the nal oor plan and:

• Rcmmdd umbr accss pits dd

• Rcmmdd cati c-rdiats r accss pits

• nam/ MAC addrss accss pits

• Cha/SSID acatd• Height of the access point/antenna above oor level

• Type of the antenna and its specications

Phas III: Survyi Phas

Thuh Wi-fi Pai ts ca prdict sia ad

prrmac, it is rcmmdd that ths rsuts b

veried with a eld survey before any permanent wireless

dpymt. Th actua Rf virmt ca b actd

by th prsc itrri dvics (802.11 as w as

-802.11), accss pits istad by a ihbr ad

virmt chas ik addi r mvi a mta

shelf. Without an actual eld survey, users won’t be able

t dtrmi th tru impact th Rf virmt

thir twrk’s prrmac.

Th Survyi Phas cvrs svra aras:

• Prrmi activ ad passiv Survys

• Maai itrrc

• estabishi QS r a d usrs

• estabishi strict scurity

• Pai r utdrs, i cssary

t autmaticay md th virmt basd th sit

oor plan. Users mark Wi-Fi coverage areas and areas

whr APs cat b pacd; spciy th miimum sia

cvra xpctd ad thr paramtrs. Th stwar

th autmaticay pacs th rquird umbr APs at

the appropriate locations on the oor map, making the

prcss simp ad quick.



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trasmit pwr th AP ca b turd up r a w AP

ca b addd. But ithr way, y a sma umbr

variabs (a si AP t a particuar cati ad adaptr)

mattr. Itrrc, th thr had, is mr cmpx.

Th cts itrrc ca b additiv such that sma

amuts itrrc rm svra surcs ca cmbi

t crat a ar itrrc at a particuar cati. This

mas th twrk maar ds t accut r a

pssib surcs itrrc, which wud icud a

APs i th sam r ihbri chas.

T mak mattrs wrs, itrrc ca cm rm

surcs thr tha Wi-fi dvics such as micrwav

vs, crdss phs, Rf jammi dvics, fHSS

dvics, Butth dvics ad may thrs. This mas

that t udrstad itrrc i th twrk,

ds t visuaiz ad udrstad th wh wirssvirmt. Whi this ca sud ik a dauti task, it

ca actuay b d quit asiy with th riht ts.

AirMat abs usrs t maa

itrrc i svra ways:

• Viw th ovrap Btw accss pits

Ay APs that ar th sam cha ad rativy

str i th sam ara wi itrr with ach thr. This

is a vry cmm surc itrrc ad vry asy

t visuaiz with AirMat Survy. Rcmmdatist mitiat this icuds, chai th APs t a

-vrappi cha (rm Cha 1 t Cha 6

r xamp), rduci th AP trasmit pwr, r mvi

th AP t a w cati. This is th simpst apprach

t addrssi itrrc, but vry ctiv i may

cass.

• Cacuat th Tru Cumuativ Itrrc

As mtid arir, th cts Itrrc ca b

additiv, awi ts sma surcs itrrc

t cmbi it a mr substatia prbm. AirMatSurvy wi dispay a cr-cdd pt shwi a th

cmbid itrrc rativ t ach accss pit.

This ivs th d usr a visua cu t th aras whr

itrrc cud caus prrmac prbms r that

AP. This mthd as taks it accut sia rm APs

adjact 11b/ chas. fr xamp, th AirMat

stwar ca autmaticay cacuat th itrrc

impact a AP cha 5 athr AP cha

6. This prvids a much mr dtaid ad accurat viw

Wi-fi itrrc a iv AP.

• Prrm Spctrum Aaysis

Itrrc is t imitd t just c-cha itrrc

rm thr Wi-fi dvics. Itrrc ca cm rm

virtuay ay dvic that mits ry i th 2.4 gHz ad

5gHz bads th spctrum. T idtiy ths typs

prbms ad udrstad thir cts Wi-fi dvics

i th virmt, it is bst t us a t that prvids

this irmati, such as th AirMat Survy prduct.

It aws th usr t s a th cumuativ ry i th

spctrum ad acrss a Wi-fi chas. Th suti ca

autmaticay idtiy -Wi-fi surcs ry duri

th survy; idtiy th typ dvic that is causi th

prbm (i.. thr is a micrwav v Cha 1)and list locations on the oor plan where the devices have

b bsrvd duri th survy. Usrs ca as ai

accss t a vry imprtat mtric - th duty cyc. I vry

simplied terms, duty cycle is the available capacity for a

iv scti spctrum. Wh th duty cyc is at 50%,

w ca thik that th spctrum is ha-u (w’r ptimists).

I th duty cyc is at 100%, th spctrum is cmpty

saturatd ad uusab r siai purpss. This typ

aaysis ivs usrs a immdiat udrstadi

th Rf physics at pay i thir virmt, ad quicky

identies sources of interference that may beyond thebudaris Wi-fi.

Usrs ca visuaiz th Rf Physica ayr t viw th

avra pwr v th Rf spctrum r vry cha

i th spctrum rm withi th Survy appicati

its. This is vry hpu r pai utur cha

assimts.



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fiur 5: AirMat Survy’s Spctrum Hat Map

Pipiti Rami Aras

ev atr succssuy assciati with a accss pit,

cit dvics ctiu t sarch r wr accss pits

with bttr wirss srvics (strr sia strth,

ssr is ad itrrc). oc a accss pit with

better service is identied, the client station will associate

with th w accss pit, braki th assciatiwith th riia accss pit. This acts th vra

prrmac, as th cit may d t thruh th

r-assciatis ad r-authticati prcdur adi

to efcient hand-off problems depending on the security

mchaism dpyd.

Vic vr wirss twrks ar hit hardr as th phs

ram rm accss pit t athr ad udr w

prb, r-assciati ad r-authticati prcsss.

Th had atcy cud b aywhr rm 400 t

600ms r such phs as thy ram rsuti i pr

vic quaity ad pssiby drppd ca.

AirMagnet Survey lists areas on the oor plan where the

cit dvics ar mst iky t ram btw accss

pits.



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estabishi optima QS r a ed Usrs

It is critica that a twrk usrs jy a adquat amut

thruhput ad wirss accss pits ar arrad i

a way t icay shar th cit ad. This is why it vry

imprtat t udrstad what th appicatis ar bi

usd by cits ad what thruhput is dd.

To perform a capacity plan, the surveyor should rst

stabish th thruhput that ach d usr wi rquir

i rdr t mt his r hr twrki ds. oc th

avra d-usr rquirmts ar stabishd, th

survyr ca cacuat th maximum umbr d

usr cits that shud assciat with a accss pit

basd th tta thruhput avaiab rm th AP.

fr xamp, AirMat Survy usrs ca map ut a

scientic capacity plan and verify if a single access point

ca satisy th capacity rquirmt basd its cati

and conguration settings.

fiur 7: Aayzi usr capacity usi AirWISe

withi AirMat Survy

Light Green areawith access point

available to satisfy

user capacity

requirements

Grey areas with no

access point

available to satisfy

user capacity

requirements

fiur 6: Viwi Cit Rami Aras i

AirMat Survy

Client Roaming

Areas Marked in

Red



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fiur 8: AirMat Survy simuati sia cvra

r w catis r accss pits

Do I need access points on each oor?

Rf sias trav thruh ad arud was ad hc

th abiity t r-us th srvics a si accss pit

for multiple oors. Users can choose to deploy a lessernumber of access points or not deploy any on a few oors

in a multi-oor building, however without compromising

ay thruhput ad cvra rquirmts.

AirMat Survy hps pa r wirss dpymts i

a multi-oor building and users can observe the access

point signal bleed over between various oors.

fiur 9: AirMat Survy dispayi sia bd

over across multiple oors

RF signal Bleed

over across foors

RF Bleed over

across foors

Original access

point location

Simulate newlocation of the

access point

Duri th survy, it may b rquird t xprimt with

not only the conguration settings (channel, transmitted

pwr, tc.) ad catis accss pits, but as

csidr addi/rmvi accss pits. I th survyr

wud physicay cha th stti ach accss pits

r wud d t purchas accss pits, th survy

prcss wud b vry xpsiv ad tim csumi.

AirMat Survy aws th usr t simuat virmt

chas, withut actuay maki stti chas

th accss pit r purchasi quipmt. It ca as

aut-acat th cha sttis t rduc itrrc



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estabishi Strict Scurity

Whi satisyi th prrmac ds, Rf spia

utsid th crprat buidi shud b kpt t a

miimum, uss srvic is t b prvidd i th parki

t r a utsid ara. Taki advata th Rf

ak, uauthrizd prs ca ai accss t thcrprat twrk rm th crprat parki t r a

neighbor’s ofce. Proper physical security measures can

b impmtd t uiy such uauthrizd accss.

Crprat scurity picis must b rrrd r additia

irmati th scurity masurs t b csidrd

r th dpyd wirss twrk.

AirMat Survy usrs ca as cat uauthrizd rprrmac itsiv statis duri a survy th

oor map.

RF spillage outside

the building

fiur 10: AirMat Survy mitri Rf spia utsid

th crprat budary

Pai outdr ntwrks

City ad cmmuity wirss dpymts usi xisti

Wi-fi tchis, Msh ntwrks ad WiMax arbcmi th rm ths days. outdr twrks

bri thir w st rquirmts ad prbms t th

dpymt tab. Th usr w has t da with buidis,

trs, varid trrais, iht ps, tph ps, tc.

T mak it wrs, wathr, i siht btw th

trasmittr ad th rcivr, r spac sss r such

dpymts pay a majr r i th prrmac.

AirMat Survy prvids a varity sutis t aid i

utdr wirss dpymts. AirMat Survy usrsca prrm a sit survy r dvics prati i th

4.9 gHz spctrum r Pubic Saty us. Pubic Saty

acis (fir, Pic ad thr mrcy acis) us

th 4.9 gHz spctrum t trasr vids, maps, missi

prs imas, mrcy rprts, tc. vr a ruatd

wirss spctrum.



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AirMat Survy usrs ca vra nMeA cmpiat

gPS dvics t cct cati irmati duri th

survy. AirMat Survy ca utiiz Micrst® Map-

pit’s r Virtua earth’s rsurcs ad auch strt

maps ay city rm withi th prduct its. AirMat

Survy as aws th usr t xprt th gPS survy

data t g earth.

I th usr sit cvrs a ar ara trrai r spas

mutip buidis, it aws th usr t bsrv th cts

trs, iht ps, tph ps ad thr bstacs

i th twrk.

fiur 11: AirMat Survy utdr survy rsuts viwd rm g earth

Phas IV: Rprti ad Si- phas

At th d th sit survyi prcss, th survyr is

rspsib r rati th Sit Survy rprt. Withut

this dcumt, th tir survyi prcss wud

b maiss. Th rprts shud prvid dtaid

irmati a actrs cssary r a succssu

deployment, as a different individual could nally install

th twrk. Th rprt wi srv as a map r th currt

rcmmdatis ad ca as act as a utur rrc

r survys ad thr dpymt chas. AirMat

Survy prvids th wi rprts:

• ovra Sia, is, Sia-t-nis irmati

basd cha/SSID

• Cha Itrrc

• Itrrc btw APs

• Rf Spctrum irmati

• Usr rquirmts (spd ad usr capacity pr AP)



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Phas V: Pridic Survys

Atr th wirss dpymt, it is critica t prrm

pridic survys t accut r chas i th

virmt, itrrc surcs, usr bhavir,

bstac chas, tc. fr xamp, a w micrwavv i th catria may icras th Rf itrrc i

a particuar ara, cai r chas i th accss pit

sttis r rcati th micrwav v. Itrducti

w accss pits by ihbrs, may rc sm

chas t b mad t th currt dpymt.

AirMat Survy’s Di Viw atur aws sid-by-sid

visuaizi dircs btw tw sparat survys.

This hps shw hw a sit’s wirss virmt has

chad vr tim. Usrs ca visuaiz dircs i

sia cvra, itrrc vs, is vs, spd,

packt sss, ram rtris, tc btw tw survys.

fiur 12: AirMat Survy’s Di Viw dispays virmt chas vr tim



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Ccusi

Tday’s wirss srvic prvidrs, maad-srvic

prvidrs, ad twrk irastructur vdrs a csidr

sit survys a madatry ad vita part th wirss

lAn dpymt prcss. With th AirMat Survy

ad Par prducts, usrs ca b assurd quickydeploying an efcient wireless network to satisfy their

busiss rquirmts. Usrs t critica irmati

th vra sia cvra, ra usr data rm activ

survys, usr capacity ad scurity th twrk.

Abut AirMat, Ic.

AirMat Ic. is th adr i scurity, prrmac ad

cmpiac sutis r wirss lAns. Th cmpay’s

ivativ prducts icud AirMat etrpris,

th adi 24x7 WlAn scurity ad prrmac

maamt suti, ad AirMat laptp Aayzr— which is kw as th “d act t r wirss lAn

trubshti ad aaysis.” othr prducts prvid

WlAn sit survy ad dsi, Rf itrrc dtcti,

remote diagnostics, and the world’s rst voice over

Wifi aaysis suti. AirMat has mr tha 6,000

custmrs wrdwid, icudi 75 th frtu 100.

The company, based in Sunnyvale, Calif., has ofces

wrdwid. fr mr irmati, visit

www.airmat.cm.

© Cpyriht 2007. A Rihts Rsrvd. AirMat® ad AirWISe® ar ristrd tradmarks, ad th AirMat is a tradmark

AirMat, Ic. A thr prduct ams mtid hri may b tradmarks thir rspctiv cmpais.

Ctact Us

T rqust r mr irmati pas ca:

Crprat Hadquartrs

1325 Chsapak Trrac

Suyva, CA 94089 - Uitd Stats

T: +1 408.400.0200fax: +1 408.744.1250

www.AirMat.cm

eMeA Hadquartrs

St. Mary’s Curt Th Bradway, Amrsham

Buckihamshir, HP7 0UT - Uitd Kidm

T: +44 1494 582 023

fax: +44 870 139 5156



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