design and deployment od wireless networked embeddd systems · concept/theory location management...

24-Aug-05

Design and Deployment of Wireless Networked Embedded SystemsJan Beutel

2

Visions 1991 1999 20001996 20032001 2004

Wireless Sensor Networks

Applications 20042000 20032001

Military Surveillance

ZebraNetSensor Webs

Argo

Duck Island

Shooter LocalizationJames Reserve

UbiquitousVision

PicoRadioWireless Overlay

PaintableComputing

Scale FreeNetworks

Terminodes

Smart DustDirectedDiffusion COTS Dust

3

Visions 1991 1999 20001996 20032001 2004

Wireless Sensor Networks

Applications 20042000 20032001

Military Surveillance

ZebraNetSensor Webs

Argo

Duck Island

Shooter LocalizationJames Reserve

UbiquitousVision

PicoRadioWireless Overlay

PaintableComputing

Scale FreeNetworks

Terminodes

Smart DustDirectedDiffusion COTS Dust

ProductionApplications

Prototypes, Experiments and Research Demos

4

Thesis Contributions

Deployment-support networkOperational conceptFeasibility study, experiments

Design and Development

Prototype and Pilot

Launch and Ramp Production Service and

SupportConcept/Theory

Location managementMeasurements and simulationAlgorithmsFunctional and qualitative requirements

BTnode platform for fast-prototypingMetrics and comparison of existing platformsDesign of hard- and software based on standardized interfaces and event driven interaction

Bluetooth scatternetsConnected multihop networksTopology control mechanismsExperiments

5




Prototype and Pilot






6

Wireless Sensor Network Systems Today

7

Large application domainNo unified one-size-fits-all solution [Römer2004]

Automated tools common in EDA communityE.g. semi-automatic design space exploration [Künzli2005,Anliker2004]

Current WSN community approachDevice characterization, e.g. Mote family [Polastre2005,Shnayder2004]

Tiered architectures [Estrin2003], WSN device classes [Hill2004]

Good platform?Suitable solution?Optimum match?

Metrics of WSN Platforms

Applications ?

8

Large application domainNo unified one-size-fits-all solution [Römer2004]

Automated tools common in EDA communityE.g. semi-automatic design space exploration [Künzli2005,Anliker2004]

Current WSN community approachDevice characterization, e.g. Mote family [Polastre2005,Shnayder2004]

Tiered architectures [Estrin2003], WSN device classes [Hill2004]

Good platform?Suitable solution?Optimum match?

Metrics of WSN Platforms

ApplicationsRequirementPlatform MetricsComparisons

9

State-of-the-Art Platforms – System Core

Mica2

Tmote Sky

Mica2Dot

Imote

10


Mica2

Tmote Sky

Mica2Dot

Imote

11


Mica2

Tmote Sky

Mica2Dot

Imote

12


Mica2

Tmote Sky

Imote

Mica2Dot

13

Lack of Flexibility


Mica2

Tmote Sky

Mica2Dot

Imote

14

State-of-the-Art Platforms – Radio Systems

Mica2

Tmote Sky

Mica2Dot

Imote

15


Mica2

Tmote Sky

Mica2Dot

Imote

16


Mica2

Tmote Sky

Mica2Dot

Imote

17


Mica2

Tmote Sky

Imote

Mica2Dot

18

2 st

rate

gies

Packet oriented

Bitstream oriented

Event-based Interaction

Rea

l-tim

e pr

oces

sing


Mica2

Tmote Sky

Mica2Dot

Imote

19

State-of-the-Art Platform Comparison

ImoteTmote SkyMica2Dot

System Core

Mica2

Radio Systems

20

State-of-the-Art Platform Comparison

ImoteTmote SkyMica2Dot

System Core

Mica2

Radio Systems

Is there room for another platform?

Multipurposeradio?

Balancedcomputing resources?

21




Prototype and Pilot






22

The BTnode Platform

Prototype

IO/Peripherals

2nd Generation 3rd Generation

Communication Computation

23

58 mm

BTnode rev3 Architecture Details

32.5

mm

System coreAtmel ATmega128256 kB SRAMGeneric IO/PeripheralsSwitchable power supplies

Dual radio system

Bluetooth radio2.4 GHz Zeevo ZV4002

Low-power radio433-915 MHz ISMChipcon CC1000

24

State-of-the-Art Platforms Comparison

Tmote SkyMica2Dot Imote BTnode rev3

System Core

Mica2

Radio Systems

25

State-of-the-Art Platforms Comparison

Tmote SkyMica2Dot Imote BTnode rev3

System Core

Mica2

Radio Systems

26

BTnut System Software

Versatile and flexible fast-prototypingLightweight operating system support in plain CLinux-to-AVR embedded emulationDemo applications and tutorial

simulate

emulate upload

compile

Built on top of multi-threaded Nut/OS frameworkNon-preemptive, cooperativemulti-threading

Events, timersPriorities for threadDynamic heap allocationInterrupt driven streaming I/O

27

Industrial technology transferCommercialization with ETH spin-off “Art of Technology”Commercial replicas resulting from open source policy

BTnodes in EducationDifferent labs and demosGraduate lab in embedded systems (120 participants)30-40 successfully completed student projects

BTnodes in Research Domains25+ wearable and ubiquitous computing applications and demosWireless (sensor) network research40+ scientific publications based on or related to BTnodes

BTnode Platform Success

0 100 200 300 400 500 600 700 800 900 100010

15

20

25

30

35

40

45

50

Slave sniff

Master sniff

Slave active

Master active

mA

samplesStandby

BTnode dev kit € 500

28




Prototype and Pilot






29

Deployment of Network Services

Example: Location Management Finding position based on radionavigationRobust network-based trilateration

Robust connectivityReliable data link layer

Service deployment functions Re-programmingSupervision, control and monitoringMeasurements, benchmarking

Requirement

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Bluetooth Multihop Network Topologies

Constructing ad hoc network topologiesLarge networks, many devicesAll devices connectedTransparent multihop transport

Scatternet formation algorithmsBlueMesh [Petrioli2002], BlueStars [Petrioli2003], BlueRings [Foo2002], BlueTrees [Zaruba2001], mesh topologies [Guerin2003]

Single-hop connectivity [Law2003]

Complexity analysis [Law2003,Vergetis2003], comparative study [Basagni2004]

Mostly static, no (large-scale) implementation reports

31

Bluetooth Multihop Network Topologies

Initial experimentsTime-multiplexed, dumbbell-like connections

XHOPLarge, connected topologiesSimple, top-down tree-building

TreeNetDistributed tree topology formationRandom connection pointsStreaming data

DSNtrees

32

Simple Scatternet Tree Construction

Link layer connectivityRandom search and connect

Distributed coordinationInquiry() and connect() operations can exhibit long delaysNo a priori guarantee for successSerialization of parallel processes

loop {while (my_slaves < max_degree) dofound_nodes = inquiry();forall nodes in found_nodes doconnect();

}}

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}}

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}}

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}}

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}}

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Making a Seven Line Algorithm Work

+ Adaptation to devicesRoot lockup, cycle elimination

+ Error handlingDeadlocks, timeouts

+ Robustness, performanceGreedy behavior, heuristics

loop {while (my_slaves < max_degree) do

found_nodes = inquiry();forall nodes in found_nodes do

connect();}

}

#define HEX2BYTE(c) ((u_char)(((c)<='9') ? (c)-'0' : tolower(c) - 'a' + 10))typedef struct _jaws_stack {

FILE *uart_terminal;HANDLE table_changed_event;bt_addr_t my_addr;struct btstack* bt_stack;bt_l2cap_stack_t *l2cap_stack;

} jaws_stack_t;jaws_stack_t* _jaws_stack;//int foo __attribute__ ((section (".noinit")));//int foo2 __attribute__ ((section (".eeprom")));void bt_print_bt_addr(bt_addr_t addr)

DEBUGT("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x", addr[5], addr[4], addr[3], addr[2], addr[1], addr[0]);const char *bt_addr_to_string( char *buf, bt_addr_t addr)

sprintf_P( buf, PSTR("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x"),addr[5], addr[4], addr[3], addr[2], addr[1], addr[0]);

return buf;}u_char* string_to_bt_addr(u_char* str, u_char* addr){

char i;u_char *strp = str;// skip whitespacewhile(*strp == ' ')

strp++;for(i = BD_ADDR_LEN-1; i >= 0; i--){

if(isxdigit(strp[0]) && isxdigit(strp[1])){addr[(u_char) i] = HEX2BYTE(strp[0]) << 4 |

HEX2BYTE(strp[1]);strp+=2;

}else{break;

}// skip ':'if(i > 0){

if(*strp == ':')strp++;

elsebreak;

}}

u_char get_uart_errors(FILE* stream){u_long parameter;u_char errors;// check driver status_ioctl(_fileno(stream), UART_GETSTATUS, &parameter);

if (parameter & UART_ERRORS) {errors = (u_char) (parameter & UART_ERRORS);// set error flags back to normalparameter = UART_ERRORS;_ioctl(_fileno(stream), UART_SETSTATUS, &parameter);

+ Application supportBasic OS functionsDebugging, visualization, monitoringStepwise testing + deployment

39

Making a Seven Line Algorithm Work

+ Adaptation to devicesRoot lockup, cycle elimination

+ Error handlingDeadlocks, timeouts

+ Robustness, performanceGreedy behavior, heuristics

loop {while (my_slaves < max_degree) do

found_nodes = inquiry();forall nodes in found_nodes do

connect();}

}

#define HEX2BYTE(c) ((u_char)(((c)<='9') ? (c)-'0' : tolower(c) - 'a' + 10))typedef struct _jaws_stack {

FILE *uart_terminal;HANDLE table_changed_event;bt_addr_t my_addr;struct btstack* bt_stack;bt_l2cap_stack_t *l2cap_stack;

} jaws_stack_t;jaws_stack_t* _jaws_stack;//int foo __attribute__ ((section (".noinit")));//int foo2 __attribute__ ((section (".eeprom")));void bt_print_bt_addr(bt_addr_t addr)

DEBUGT("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x", addr[5], addr[4], addr[3], addr[2], addr[1], addr[0]);const char *bt_addr_to_string( char *buf, bt_addr_t addr)

sprintf_P( buf, PSTR("%.2x:%.2x:%.2x:%.2x:%.2x:%.2x"),addr[5], addr[4], addr[3], addr[2], addr[1], addr[0]);

return buf;}u_char* string_to_bt_addr(u_char* str, u_char* addr){

char i;u_char *strp = str;// skip whitespacewhile(*strp == ' ')

strp++;for(i = BD_ADDR_LEN-1; i >= 0; i--){

if(isxdigit(strp[0]) && isxdigit(strp[1])){addr[(u_char) i] = HEX2BYTE(strp[0]) << 4 |

HEX2BYTE(strp[1]);strp+=2;

}else{break;

}// skip ':'if(i > 0){

if(*strp == ':')strp++;

elsebreak;

}}

u_char get_uart_errors(FILE* stream){u_long parameter;u_char errors;// check driver status_ioctl(_fileno(stream), UART_GETSTATUS, &parameter);

if (parameter & UART_ERRORS) {errors = (u_char) (parameter & UART_ERRORS);// set error flags back to normalparameter = UART_ERRORS;_ioctl(_fileno(stream), UART_SETSTATUS, &parameter);

Seven lines

2000 lines~87 kbyte + Application support

Basic OS functionsDebugging, visualization, monitoringStepwise testing + deployment

40

DSNtrees – Field Experiments

Deployment using 70+ nodes on an office floor

Largest connected Bluetooth Scatternet

41




Prototype and Pilot






42

WSN Development Reality

It is hard to deploy anywhere beyond 10-20 nodes today.

Coordinated methods and tools are missing today.

43

Virtualization and EmulationEmStar [Ganesan2004]

BEE [Chang2003,Kuusilinna2003]

Today's Design and Development

Sca

le

Figure abridged from D. Estrin/J. ElsonReality

SimulationTOSSIM [Levis2003]

PowerTOSSIM [Shnayder2004]

Avrora [Titzer2005]

Test GridsmoteLab [Werner-Allen2005]

Emstar arrays [Cerpa03/04]

Kansei [Dutta2005]

44

Virtualization and EmulationEmStar [Ganesan2004]

BEE [Chang2003,Kuusilinna2003]

Today's Design and Development

Sca

le

Figure abridged from D. Estrin/J. ElsonReality

SimulationTOSSIM [Levis2003]

PowerTOSSIM [Shnayder2004]

Avrora [Titzer2005]

Test GridsmoteLab [Werner-Allen2005]

Emstar arrays [Cerpa03/04]

Kansei [Dutta2005]

DeploymentIn-network reprogramming [Levis2004,Hui2004]

Calibration and Verification[Szewczyk2004]

Trial-and-error [Mainwaring2004,Hemingway2004,Cerpa2001]

Dependence on infrastructure[Szewczyk2004]

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Target Sensor Network

Next-Generation Deployment-Support

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47



48



49



Developer Workstation

Deployment-Support NetworkTemporary, minimal invasiveVirtual connections to nodesReliable, wireless, scalable

50

Publications

Deployment-support networkSenSys 2004 [BDH04]IPSN 2005 [BDMT05]


Prototype and Pilot



Location managementICASSP 2001 [SRB01] Handbook on Sensor Networks [Beu04]

BTnode platform for fast-prototypingISWC 2002 [PEW02]Personal and Ubiquitous Computing [PEW03]SenSys 2003 [BKR03]EWSN 2004 [BKM04]IEEE Transactions on Computers [ABD04] Bluetooth scatternets

SenSys 2004 [BDH04] Computer Communications [Beu05]

design and deployment od wireless networked embeddd systems · concept/theory location management...

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