Wilamowski B.M., Irwin J.D. The Industrial Electronics Handbook. Second Edition: Industrial Communication Systems

Подождите немного. Документ загружается.

50-2 Industrial Communication Systems

network.topologies.such.as.star,.tree,.and.mesh..ZigBee.devices.can.act.as.coordinators.that.initiate.

anetwork,.a.device.with.routing.capability,.or.as.an.end.device.with.no.routing.capability.

802.15.4

.is.also.the.basis.for.wireless.sensor.networks.(WSN).and.mesh.networking.(see.Section.50.5)..

Wireless.mesh.networks.(WMN).are.an.eective.solution.for.building.automation.and.control..A.WMN.

would.enable.maintenance.workers.using.mobile.handheld.devices.such.as.smartphones.or.personal.

digital.assistants.to.gather.data.from.wherever.they.are.in.a.building.

.mesh.access.points.(MAPs).communicate.only.with.their.adjacent.routers..In.larger.mesh.net-

work

.deployments,.some.of.the.access.points.(APs).would.act.as.intermediate.routers.or.relays.between.

APs.(multi-hopping).not.within.wireless.range.(non-line-of-sight).of.one.another..When.an.intermedi-

ate

.router.becomes.faulty,.other.routers/APs.adapt.and.pick.up.the.routing;.i.e.,.the.mesh.network.is.self.

healing,.ensuring.constant.availability.of.information.

50.3 ZigBee in the Context of Other Wireless Networks

Zigbee. belongs.to. lowest.range/data. rate.wireless.technologies.. Figure. 50.2. illustrates. some.general.

dierences. among. wireless. personal. area. networks. (WPANs),.wireless. metropolitan. area. networks.

(WMANs),.wireless.local.area.networks.(WLANs),.and.wireless.wide.area.networks.(WWANs).

. is. also. benecial. to. compare. ZigBee. against. other. wireless. technologies. relative. to. its. range,.

throughput,.power.consumption,.and.cost..Table.50.1.provides.such.brief.overview.

50.4 ZigBee Stack

Although.based.upon.standard.seven-layer.open.systems.interconnection.(OSI).mode,.ZigBee.stack.

denes.specic.layers.responsible.for.performing.of.specic.set.of.services.to.the.layer.above.it.through.a.

service.access.point.(SAP)..While.IEEE.802.15.4.standard.denes.two.lower.layers—the.physical.(PHY).

and.the.medium.access.control.(MAC).sub-layer,.the.ZigBee.Alliance.builds.on.this.foundation.by.pro-

viding

.the.network.(NWK).layer.and.the.framework.for.the.application.layer.(APL)—application.sup-

port

.(APS).sub-layer,.the.ZigBee.device.object.(ZDO),.and.the.manufacturer-dened.application.objects.

(Figure.50.3).. e.details.on.these.layers.will.be.further.elaborated.in.following.sections.

Mesh network

applications

ZigBee applications

ZigBee profiles

ZigBee app layer

ZigBee network layer

IEEE802.15.4 wireless microcontroller

IEEE802.15.4 MAC Simple wireless networks

Mesh networks

Co-existence

Interoperability

Simple network

applications

Level 3

Level 2

Level 1

FIGURE 50.1 IEEE.802.15.4.and.ZigBee.protocol.stacks.

ZigBee 50-3

50.5 IEEE 802.15.4

 e.goal.of.the.IEEE.802.15.4.task.group.is.to.dene.the.PHY.and.MAC.layers.specications.for.low-

cost,

.low.data.rate.and.hence,.low-complexity.wireless.connectivity.of.mobile.or.stationary.devices.with.

limited.battery.capability.

.relationship.between.IEEE.802.15.4.and.ZigBee.is.that.ZigBee.makes.use.of.the.IEEE.802.15.4.

standard.for.the.lower.two.OSI.layers.(PHY.and.MAC.layers).and.species.the.upper.layers.as.well.as.

being.the.name.for.the.whole.technology.from.a.marketing.perspective.where.ZigBee.stands.for.the.full.

technological.solution.based.upon.IEEE.802.15.4.

.key.features.of.IEEE.802.15.4.are

•

. 2.4.GHz.and.868/915.MHz.frequency.band.options

•

. Support.for.star.and.peer-to-peer.topologies;.therefore,.supports.a.wide.variety.of.routing.proto-

cols

.and.topologies

Wireless communication landscape

WPAN

WLAN

WMAN

WWAN

IEEE 802.15.1: Bluetooth

Class 1

Class 2

Class 3

ZigBee

802.11a

WiFi

WiMAX

Cellular Networks

TETRA

GSM

GPRS

EDGE

Fixe (IEEE 802.16-2004)

Mobile (IEEE 802.16e)

WiBro (Wireless Broadband: Korean standard)

DECT

HiperLAN

–

802.11b

802.11g

802.11n

WirelessMAN IEEE 802.16

Mobile Broadband Wireless Access (MBWA) (IEEE 802.20)

Wireless Regional Area Networks (WRAN) (IEEE 802.22)

IEEE 802.15.4

OCARI

WirelessHART

ISA100.11a

FIGURE 50.2 Wireless.technology.landscape.

TABLE 50.1 A.Comparison.of.LR-WPAN.with.Other.Wireless.

Technologies

WLAN.

(802.11)

Bluetooth-Based.

WPAN.(802.15.1)

Low-Rate.WPAN.

(802.15.4)

Range

∼100

.m ∼10–100.m ∼10.m

Data

.throughput

∼2–11

.Mbs ∼1.Mbs ∼0.25.Mbs

Power

.consumption Medium Low Ultralow

Size Larger Smaller Smallest

Cost/complexity >6 1 0.2

50-4 Industrial Communication Systems

•. Contention-based.channel.access,.CSMA/CA

•

. Message.transmission.can.be.fully.acknowledged

•

. Beacon.from.15.ms.up.to.4.min,.allowing.very.low.duty.cycles.

•

. Optional.guaranteed.time.slots.(GTSs).can.be.reserved

•

. 16.bit.address.eld.or.extended.64.bit.addresses

•

. Link.quality.indication.byte.is.attached.to.each.receiver

50.5.1 Physical Layer

 ere. are. two. groups. of. frequency. bands. specied:. 2.45.GHz. and. 868/915.MHz.. e. popularity.

of2.45.GHz.is.very.high.compared.to.the.868/915.MHz.solutions.that.require.dierent.hardware.and.

cannot.just.be.switched.by.soware.(Figure.50.4).

Channel 0

Channels 1–10

915 MHz

868.3 MHz

Kanal 11–26

902 MHz

2.45 GHz 2.4835 GHz2.4 GHz

928 MHz

5 MHz

2 MHz

FIGURE 50.4 Frequency.spectrum.

Physical (PHY) layer2.4 GHz radio 868/915 MHz radio

Medium access control (MAC) layer

PD-SAP

PLME-SAP

Network (NWK) layer

Security

management

Message

broker

Routing

management

Network

management

Application support sublayer (APS)

ZDO Management

plane

APS message

broker

Reflector

management

APS security

management

Zigbee device object

(ZDO)

Application (APL) layer

Application framework

. . .

ZDO public

interfaces

APSME-

SAP

NLME-

SAP

Endpoint 1

APSDE-SAP

Endpoint 0

APSDE-SAP

Endpoint 240

APSDE-SAP

MLME-SAP

NLME-SAP

MLDE-SAP

NLDE-SAP

Security

service

provider

ZigBee

IEEE 802.15.4

(End

manufacturer

defined)

Application

object 240

(End

manufacturer

defined)

Application

object 1

FIGURE 50.3 ZigBee.stack.

ZigBee 50-5

 e.radios.in.the.2.4.GHz.spectrum.use.direct.sequence.spread.spectrum.(DSSS),.which.is.managed.by.

the.digi

tal

.stre

.into.the.modu

lator.

.Bina

.phase.shi.keyi

.(BPS

.is.used.in.the.868.and.915.MHz.

band

.and.orth

ogonal

.quad

rature

.phase.shi.keyi

.(QPS

.that.tran

smits

.two.bits.per.symb

.is.used.in.

the.2.4.GHz.band.(Tab

.50.2)

Transmission

.rang

.may.vary.betw

een

.30.m.indo

.and.100.m.outd

oor

.as.a.rule.of.thumb

.alth

ough

it.is.heav

ily

.depe

ndent

.on.the.part

icular

.envi

ronment

.and.may.vary.acco

rdingly.

. e.maxi

mum

.outp

powe

.of.the.radi

.is.gene

rally

.+3.dBm.and.can.be.incr

eased

.with.an.exte

rnal

.ampl

ier

.up.to.20.dBm..

Solu

tions

.with.high

-sensitivity

.tran

sceivers

.(−10

.dBm.in.2.4.GHz.and.−110.dBm.in.868/

915

.MHz).and.

powe

.amp

liers

.(+1

0–20

.dBm).hav

.pro

ven

.to.rea

.ove

.4.km.out

doors

.[Me

shnetics].

50.5.2 MaC Layer

From.the.data.link.layer.aer.OSI,.the.IEEE.802.15.4.denes.only.the.lower.part.of.the.layer,.which.is.the.

MAC.laye

. e.impl

ementation

.of.the.logi

cal

.link.cont

rol

.(LLC

)

.has.not.been.speci

ed

.in.IEEE.802.

15.4.

.basi

.chann

.acce

.mode.is.carr

ier

.sens

.mult

iple

.acce

.with.coll

ision

.avoi

dance

.(CSM

A/CA).

. ere.

are.thre

.nota

ble

.exce

ptions

.to.the.use.of.CSMA

.Beac

ons

.are.sent.on.a.xed.timin

.sche

dule

.and.do.not.use.

CSMA

.Mess

age

.ackn

owledgments

.also.do.not.use.CSMA

.Fina

lly,

.devi

ces

.in.beac

on-oriented

.netw

orks

.that.

have.low-

latency

.real

-time

.requ

irements

.may.also.use.GTSs

.which.by.den

ition

.do.not.use.CSMA

 ere

.are.two.basi

.mod

.of.ope

ration

.tha

.ae

.the.cha

nnel

.acc

ess

.str

ategy:

•

. Unsl

otted

.mod

.(no

n-beacon-enabled)

•

. Slot

ted

.mod

.(be

acon-enabled)

50.5.2.1

Unslo

tted Mode

.non-

beacon-enabled

.netw

orks,

.an.unsl

otted

.CSMA

/CA

.chan

nel

.acce

.mech

anism

.is.used

.In.this.type.

of.netw

ork,

.ZigB

.rout

ers

.typi

cally

.have.thei

.rece

ivers

.cont

inuously

.acti

ve,

.requ

iring

.a.more.robu

.powe

supp

ly.

.Howe

ver,

.this.allo

.for.hete

rogeneous

.netw

orks

.in.whic

.some.devi

ces

.rece

ive

.cont

inuously,

.whil

othe

.only.tran

smit

.when.an.exte

rnal

.stim

ulus

.is.dete

cted.

.Befo

.each.tran

smission,

.the.send

.chec

.by.

CSMA

/CA

.if.the.chan

nel

.is.occu

pied

.and.send

.its.data.by.a.rand

.time.ose

.if.the.chan

nel

.beco

mes

.free

Opti

onally,

.it.can.indi

cate

.to.the.rece

iver

.if.an.ACK.is.desi

red.

.In.this.mode

.no.netw

ork

.main

tenance

.by.a.

PAN.coor

dinator

.node.is.requ

ired.

. ere.are.thre

.basic.comm

unication

.scen

arios:

•

. Data.are.sent.from.part

icipating

.node

.to.the.PAN.coor

dinator.

.In.this.case

.the.PAN.coor

dinator

is.alwa

.in.list

ening

.mode.and.is.not.allo

wed

.to.ente

.slee

.mode

.PAN.coor

dinators

.are.typi

cally

not.bat

tery

.pow

ered.

TABLE 50.2 Physical.Channel.Properties

Channel.Parameters Data.Parameters

Spreading.Parameters

Frequency.

Band Bandwidth Ch..Nr. Region

Raw.Data.

Rate

Symbol.

Rate Symbols Chiprate Modulation

868–

868.6

.MHz

300.kHz 0 E

urope 20

.kbps 20.

kBaud

Bin

ary 300

kchips/s

PSK

902–

928

.MHz

600.kHz 1–10 USA

.kbps 40.

kBaud

Bin

ary 600

kchips/s

PSK

2400–

2483.5

.MHz

2.MHz 11–26 W

orldwide 250

.kbps 62,5.

kBaud

16.ort

hog. 2

.Mchi

ps/s Oset-QPSK

Shows.the.physical.channel.properties.from.the.IEEE.802.15.4-2003.. e.updated.IEEE.802.15.4-2006.has.only.been.

implemented.on.a.few.chip.solutions.like.the.Atmel.AT86RF231.and.the.AT86RF212..Among.other.things,.it.enhances.the.

data.rate.in.the.868.and.915.MHz.band.to.100.and.250.kbps,.respectively,.by.using.Oset-QPSK.modulation.with.chip.rates.

of.400.and.1000.kchips/s.

50-6 Industrial Communication Systems

•. Data.are.sent.from.one.participant.to.another.(peer-to-peer-topology)..As.in.the.rst.scenario,.the.

receiver.must.always.be.capable.of.receiving.

•

. Data.are.sent.from.the.PAN.coordinator.to.one.participant.. e.participant.asks.periodically.

for.data.at.the.coordinator.. e.coordinator.sends.an.ACK.and.the.data.if.something.is.avail-

able,

.otherwise.it.sends.a.null.packet.. e.coordinator.is.always.in.receiving.mode.when.not.

transmitting.

50.5.2.2

Slotted Mode

.the.slotted.mode,.there.is.a.superframe.structure.coordinated.by.the.PAN.coordinator.as.the.trans-

mitter

.of.periodic.beacons.. e.superframe.is.started.by.the.beacon.(without.using.CSMA/CA).and.

followed.by.16.equal.time.slots.. e.beacons.are.used.to.synchronize.the.attached.devices.to.identify.the.

PAN.and.to.describe.the.structure.of.the.superframes.

For

. low-latency. applications,.the.PAN. coordinator. may.optionally. dedicate.portions.of.the.active.

superframe.to.GTSs.. e.GTSs.form.the.contention-free.period.(CFP),.which.always.appears.at.the.end.

of.the.active.superframe.. e.other.slots.are.right.aer.the.beacon.and.are.the.so-called.contention.access.

slots..Any.device.wishing.to.communicate.during.the.contention.access.period.(CAP).between.two.bea-

cons

.has.to.compete.with.other.devices.using.a.slotted.CSMA/CA.mechanism..All.transactions.have.to.

be.completed.by.the.time.of.the.next.network.beacon.. e.rst.nine.slots.shall.always.be.CAP.slots,.which.

can.be.used.by.any.device,.while.the.following.optional.up.to.seven.slots.may.be.allocated.by.the.coordi-

nator

.for.individual.devices.upon.a.request..Figure.50.5.shows.the.concept.of.the.superframe.structure.

With

.the.superframe.order.(SO).parameter,.the.superframe.can.be.divided.in.an.active.and.inactive.

phase.. e.active.phase.consists.of.16.identical.time.slots.as.described.above.followed.by.the.inactive.

phase.where.the.PAN.coordinator.as,.of.course,.also.the.other.participants.can.enter.a.low.power.sleep.

mode.to.save.batteries.. is.is.an.improvement.compared.to.the.unslotted.mode;.however,.it.comes.with.

a.higher.synchronization.eort..Also.here,.there.are.three.basic.communication.scenarios:

•

. Data.are.sent.from.participating.nodes.to.the.PAN.coordinator.. e.participant.tries.to.obtain.a.

CAP.slot.with.CSMA/CA.if.no.GTS.for.it.has.been.dened.in.the.superframe.structure..If.a.GTS.

has.been.reserved,.it.can.send.data.immediately.aer.synchronizing.to.its.slot.

•

. When.a. peer-to-peer. communication.is. initiated,. participants. synchronize.themselves. before.

transmitting.the.data.in.one.of.the.CAP.slots.

•

. If.data.are.sent.from.the.PAN.coordinator.to.one.participant,.it.shows.this.information.in.the.fol-

lowing

.beacon.. e.participant.listens.periodically.to.the.beacons.and.responds.in.the.CAP.slots.

to.pick.up.the.data.

Beacon

Contention

access period

(CAP)

Optional

guaranteed

time slots (GTS)

8 9 10 15

Inactive

Superframe duration

FIGURE 50.5 Superframe.

ZigBee 50-7

50.5.3 Network Layer

Network.layer.(NWK).enables.routing.and.multi-hop.communication.between.devices.in.star,.mesh,.or.tree.

topology.. e.NWK.provides.two.types.of.basic.services;.data.services.and.management.services.. e.data.

services.include.a.network.layer.protocol.data.unit.(NPDU),.transmitting.NPDU.to.the.next.hop,.and.apply-

ing

.NWK.security.. e.management.services.allow.applications.to.interact.with.the.ZigBee.protocol.stack..

 e.management.services.include.conguring.a.new.device,.establishing.a.new.network,.joining.and.leaving.

a.network,.assigning.address.to.devices.joining.the.network,.neighborhood.discovery,.and.route.discovery.

.devices.in.a.ZigBee.network.are.either.reduced.function.device.(RFD).or.full.function.device.(FFD)..

RFD.is.simple.in.terms.of.hardware.and.soware.complexity..It.is.only.restricted.to.start.topology,.is.inca-

pable

.of.network.routing,.is.low.power,.and.is.potentially.low.cost.because.of.reduced.functionality..On.

the.other.hand,.FFD.is.more.resourceful,.has.routing.capability,.and.is.generally.powered.by.mains.power.

supply..RFD.only.communicates.with.FFD.while.FFD.can.communicate.with.another.FFD.and/or.RFD..

ZigBee.devices.are.logically.divided.into.three.dierent.classes;.an.end.device,.a.router,.and.a.coordinator.

(Figure.50.6).

.responsibilities.of.a.PAN. coordinator.comprise. initiating.new.network,.managing. the.network.

nodes,.and.storing.network.information,.for.instance,.security.keys.. ere.is.exactly.one.PAN.coordinator.

per.ZigBee.network.and.is.an.FFD..Router.is.an.optional.FFD.component.in.ZigBee.network.and.is.used.to.

extend.network.coverage,.allocation.and.de-allocation.of.addresses,.and.routing.between.nodes..End.devices.

implement.user.applications.and.can.either.be.FFD.or.RFD.but.do.not.participate.in.data.forwarding.

.start.topology,.communication.is.done.only.through.PAN.coordinator.and.follows.a.master/slave.

paradigm..In.mesh.topology,.any.device.can.talk.to.any.other.device..Such.a.topology.is.ad.hoc,.self-

organizing,

.and.self-healing,.and.employs.multi-hop.communication..Mesh.topology.allows.multiple.

paths.from.a.given.source.to.destination.and.thus.increases.reliability..If.one.breaks,.the.data.are.sent.

via.another.path.transparently..Cluster-tree.topology.is.a.hybrid.(star.plus.mesh).approach.where.PAN.

coordinator.designates.itself.as.a.cluster-head.and.forms.a.tree.around.itself..Although.such.a.topology.

increases.coverage.area,.it.introduces.additional.delays.

.routing.algorithms.that.are.used.in.ZigBee.networks.are.hierarchical.and.have.potential.for.table.

optimizations..Commonly.used.algorithms.include.a.routing.algorithm.similar.to.Ad-hoc.on-demand.

distance.vector.(AODV).and.cluster-tree.algorithm.

50.5.4 application Layer

 e. APL. of. ZigBee. protocol. stack. is. composed. of. application. support. (APS). sub-layer,. application.

framework,.and.ZDO.. e.APS.provides.an.interface.to.the.NWK.. e.services.provided.by.APS.com-

prise

.data.transmission,.fragmentation.and.reassembly,.reliable.data.transport,.security,.device.binding,.

and.maintenance.of.APS.information.base.(a.database.containing.information.about.managed.objects)..

Application.objects.(manufacturer-dened.components.that.implement.the.application).reside.in.appli-

cation

.framework..A.total.of.240.distinct.application.objects.can.be.dened.with.IDs.ranging.from.1.

Coordinator

Router

End device

Star Cluster-tree Mesh

FIGURE 50.6 ZigBee.network.topologies.and.classes.of.device.

50-8 Industrial Communication Systems

to.240;.241.to.254.are.reserved.for.future.use.while.0.and.255.are.reserved.to.identify.interfaces.(0,.data.

inte

rface

.to.ZDO

;

.255

.dat

.int

erface

.to.bro

adcast

.to.all.app

lication

.obje

cts).

ZDO

.resid

.with

.APL.and.on.the.top.of.APS.sub-

layer.

.ZDO.prov

ides

.comm

.func

tionality

.for.all.

appl

ications.

. e.mai

.res

ponsibilities

.of.the.ZDO.inc

lude

•

. Init

ializing

.APS

.NWK

.and.sec

urity

.ser

vice

.pro

vider

•

. Devi

.and.ser

vice

.dis

covery

.wit

hin

.a.sing

.PAN

•

. Mana

ging

.secu

rity

.by.empl

oying

.key.mana

gement

.like.key.esta

blishment,

.key.tran

sport,

.key.

requ

est,

.and.upd

ating

.and.rem

oving

.dev

ice

•

. Mana

ging

.net

work

.by.cla

ssifying

.dev

ices

.into.coo

rdinator,

.rou

ters,

.and.end.dev

ices

•

. Creating.and.maintaining.binding.tables

•

. Node.man

agement

.for.FFD

.e.g

.ret

rieval

.of.rou

ting

.and

/or

.bin

ding

.tab

50.6 Development and Industrial applications

 e.ZigBee.specications.were.developed.by.the.ZigBee.Alliance.as.an.eort.to.establish.a.standardized.

base.set.of.solu

tions

.for.sens

.and.cont

rol

.syst

ems

.requ

iring

.low.data.rate

.and.low.powe

.cons

ump-

tion.

.Typ

ical

.app

lications

.tha

.are.tar

geted

.by.Zig

Bee

.are

•

. Home.and.bui

lding

.auto

mation

•

. Smar

.ene

rgy

TABLE 50.3 Development.Platforms.of.ZigBee.Chipset.Manufacturers

Manufacturer

Features

.Tran

sceiver

.for.

IEEE.802.15.4.

PHY Micr

ocontroller ZigBee

.Stac

ZigBee

.Pro.

Stack

bedded

Operat

ing

.Syst

for.Applic

ation

.Lay

Atmel AT86RF212

.for.

800/900.MHz.

band

T86RF231

.for.

2.4.GHz.band

AVR/AVR32.Ris

contr

oller

.wit

in-system.

progra

mmable

ash

itCloud BitCloud FreeRTOS

TinyOS

μC/OS-II

NORTi

.RTOS

reescale MC13192

.for.

2.4.GHz.ban

MC13202

.for.

2.4.GHz.ban

MC9S08GT

Flexis

.ult

ralow-

power

MC9S08QE128.

(8.bit).and.

MCF51QE128.

(32.bit)

eeStack BeeStack FreeRTOS

μC/OS-II

MC1321x

.Syst

.in.Packa

.(SiP)

MC1322x.Pla

tform

.in.a.Packa

.(PiP)

TI CC2420

.for.

2.4.GHz.ban

CC2520

.for.

2.4.GHz.ban

8051

MSP430

Z-Stack Z-Stack FreeRTOS

TinyOS

μC/OS-II

CC2430

.Syst

.on.Chip.(SoC)

CC2431.Syst

.on.Chip.(SoC)

CC2480

.ZigBe

.Netw

ork

.Pro

cessor

.wit

.Z-Stac

.+.MSP430

Emb

er EM250

.Syst

.on.Chip Em

berZNet

.Stac

k EmberZNet

Pro.Stac

FreeRTOS

TinyOS

Microchip MRF24J40/MA/

PIC18,

.PIC24,.

dsPIC,.and.

PIC32.families

icrochip

.ZigBe

2006.Pro

tocol

Stack.(AN1232)

Micro

chip

ZigBee.PRO.

(AN1255)

FreeR

TOS

ZigBee 50-9

•. Personal.health.care

•

. Telecom.services

•

. Industrial.asset.management

50.6.1 ZigBee Development Platforms

 ere.are.several.development.platforms.that.are.available.from.chipset.manufacturers.(Table.50.3).

50.6.2 Industrial applications

ZigBee.is.particularly.suitable.for.WSN.application..Examples.of.industrial.applications.of.ZigBee.are

•

. Condition-based.maintenance.for.plant.asset.management

•

. Environmental.and.structural.monitoring

•

. Teledosimetry.in.nuclear.power.plants

 ese

.applications.typically.require.scalability.and.low.power.consumption.support..Condition-based.

maintenance. possibly. requires. vibration. analysis.that.may. need. the.development.of.specic. applica-

tion

.prole.in.order.to.deal.with.data.fragmentation.because.accelerometer.sampling.rate.can.reach.the.

Wireless sensors network oriented middleware

Comm.

manager

Virtual

sensor

manager

Persistent

data

manager

Software bus (publish/subscribe)

ZigBee coordinator

(CPAN)

Network monitoring

OPC-DA

Database

ZigBee router

(FFD)

Sensor (RFD)

Industrial backbone

Publication

manager

SCADA

ZigBee coordinator

(CPAN)

OPC-UA

FIGURE 50.7 ZigBee.integration.with.global.intranet/Internet.

50-10 Industrial Communication Systems

bandwidth.limit.of.IEEE.802.15.4.PHY..Teledosimetry.requires.nomadism.support.as.the.network.node.

(the.perso

.with.his.perso

nal

.dosi

meter)

.may.be.mobi

le.

.Curr

ent

.ZigB

.speci

cations

.do.not.full

.supp

ort

mobi

lity

.with

out

.pack

.loss.becau

.of.its.inhe

rent

.limi

tation

.to.AODV.prot

ocol

.used.in.ZigB

.NWK.

.depl

.ZigB

.WSN.appl

ication

.in.larg

.scal

.one.need

.to.deve

lop

.typi

cal

.arch

itecture

.as.in.

Figu

.50.

WSN

.midd

leware

.is.an.impo

rtant

.comp

onent

.beca

use

.it.help

.to.redu

.the.powe

.cons

umption

.of.

end.dev

ices

.(se

nsors)

.by.avo

iding

.the.con

current

.req

uests

.of.the.sam

.sen

sor

.dat

.fro

.sev

eral

.app

lica-

tions.

.It.als

.hel

.to.mas

.the.com

plexity

.of.the.net

work

.topo

logy

.to.the.app

lications.

50.7 Conclusion

In.this.chapter,.an.overview.of.ZigBee.wireless.communication.technology.has.been.presented..Its.speci-

cations

.cont

inue

.to.evol

.to.take.into.acco

unt

.new.feat

ures

.and.impr

ovements,

.than

.to.feed

backs

from.manu

facturers

.and.membe

.of.the.ZigB

.Alli

ance.

.For.exam

ple,

.ZigB

.2006.and.ZigB

.2007.

are.the.two.versi

ons

.of.the.ZigB

.stac

.proto

col

.for.resid

ential

.and.buil

ding

.autom

ation

.appl

ications;

wher

eas

.ZigB

.Pro.is.targ

eted

.for.indu

strial

.autom

ation

.appl

ications.

.For.an.in-d

epth

.stud

.of.ZigB

tech

nologies,

.ref

.to.[Zi

gBee

.All

iance]

.for.mor

.det

ails

.abo

.di

erent

.Zig

Bee

.spe

cications.

references

[Meshnetics].http://www.meshnetics.com

[ZigBee

.Alli

ance]

.Zigbe

.Alli

ance,

.URL.fro

.Jan

uary

.2009:.htt

p://www.zigbee.org

51-1

51.1 Introduction

In.the.last.decade,.plenty.of.research.has.been.conducted.in.the.eld.of.wireless.sensor.networks.(WSN)..

One.impo

rtant

.part.of.a.WSN.node.is.its.comm

unication

.inte

rface.

.Star

ting

.with.prop

rietary

.comm

unica-

tion

.syst

ems

.in.earl

.days.of.WSN,.stan

dardized

.comm

unication

.inte

rfaces

.are.requ

ired

.toda

.IEEE.802.

wire

less

.pers

onal

.area.netw

ork

.(WPA

.task.Grou

.4.has.den

.a.low.data.rate.comm

unication

.prot

ocol

with.low.ener

.cons

umption.

.IEEE.802.

15.4

.den

.phys

ical

.(PHY

)

.and.medi

.acce

.cont

rol

.(MAC

)

laye

.and.is.wide

.used.in.curr

ent

.WSN.. is.stan

dard

.form

.a.basi

.for.othe

.emer

ging

.uppe

.laye

.stan

dard

.prot

ocols,

.like.ZigB

ee,

.Wire

lessHART,

.and.SP10

.Whil

.thos

.prot

ocols

.are.esta

blished

.in.home.auto-

ation,

.buil

ding

.auto

mation,

.and.fact

ory

.auto

mation,

.Inte

rnet

.prot

ocol

.(IP).conn

ectivity

.is.stil

.desi

red.

51.2 Why IP in WSN and For Smart Cooperating Objects?

IP. is. the. predominating. protocol. in. network. infrastructures. for. information. and. communication.

syst

ems,

.rang

ing

.from.loca

.area.netw

orks

.(LAN

.to.wide.area.netw

orks

.(WAN

s).

.Howe

ver,

.IPv4.is.

obso

lete

.consi

dering

.the.envi

sioned

.tril

lions

.of.devi

ces,

.whic

.will.appe

.in.the.near.futu

re.

.IPv6

.the.

-generation

.IP,.expa

nds

.addr

ess

.spac

.of.IP.to.2

128

.addresses.and.includes.miscellaneous.improvements.

base

.on.exp

eriences

.wit

.IPv

6LoWPAN: IP for Wireless

Sensor Networks and

Smart Cooperating Objects

51.1. Introduction..................................................................................... 51-1

51.2

. Why.IP.in.WSN.and.For.Sma

.Coo

perating

.Obje

cts?............. 51-1

IP.as.Open.Standard.Protocol.Instead.of.Proprietary.

Protocols. •. IPRouters.Instead.of.Complex.Gateways. •. Use.of.Already.

Existing.Protocols,.Tools,.and.Applications. •. New.Architectural.

Styles.like.Service-Oriented.Architectures. •. IP.Support.in.Operating.

Systems. •. Lessons.Learned.From.Maintaining.the.Internet

51.3. Introduction.in.802.15.4................................................................. 51-3

51.4

. 802.

15.4

.and.6Lo

WPAN.................................................................. 51-5

51.5

. 6LoW

PAN......................................................................................... 51-7

Address.Autoconguration. •. Frame.Types.and.Fragmentation. •. .

Mesh.Frame.Type. •. Broadcast.and.Multicast.Address.

Mapping. •. Header.Compression. •. Scopes. •. Summary.ofFrame.

Types.and.Compression.Schemes. •. Security

51.6. Summary..........................................................................................51-14

References....................................................................................................51-14

Guido Moritz

University of Rostock

Frank Golatowski

University of Rostock