Smart Wireless Gateways

Think Wireless…Think ELRPOThink Wireless…Think ELRPO© ELPRO Technologies© ELPRO Technologies NORCAL ISANORCAL ISA

Smart Wireless Wireless GatewaysGateways

The 21The 21stst Century modem Century modem

Frank WilliamsFrank Williams

May 1, 2007


The Plant : A complex environment Plant Servers

OtherComputingDevices

Business Management

Area Servers PlantNetworkModules

NetworkGateway

NetworkGateway

Process Management

Subnetwork Gateway

ApplicationModule

HistoryModule

Personal ComputerNetwork Manager

Control Stations

ArchiveReplay Module

AdditionalCN Modules

Fiber Optics

NetworkInterfaceModuleOther Data

Hiway Boxes

MultifunctionControllerExtendedController

BasicController

AdvancedMultifunctionController

LocalProcessors

Subnetwork CONTROL NETWORK

SmartineTransmitters

PLCGateway

OtherSubsystems

PLC

Logic Manager ProcessManager

AdvancedProcessManager

Transmitters

Control Network Extenders

Field Management

sec

msec

1 sec

secs

min

hoursCourtesy: Apprion

Adding wireless

provides opportunities,

but

presents challenges


The new competitive reality!Global competition demanding higher productivity

More data, with more intelligence, yielded from more points throughout the plant, or factory.

Basically, a new paradigm in productivity gain :

data availability when and where neededdata availability when and where needed

we have seen this before• 4-20mA Hart• Marshalling cables Foundation Field bus, Ethernet• Automation DeviceNet, Profibus, etc• Alarm systems Pagers, SMS, GSM, E-mail


Plant or Factory has more wirelessPlant or Factory has more wireless

Wireless Ethernet

Wireless I/O

•Sensors

•Analog / digital

•Pulse / Freq

•Pressure / Flow

Wireless Data

•PLC to PLC

•DCS to Remote

•PLC/DCS to HMI

•Protocol connectivity

Wireless finds new applicationsWireless finds new applicationsWith greater reliabilityWith greater reliabilityAnd more flexible at less costAnd more flexible at less cost


The largest constraint to collecting information is …The largest constraint to collecting information is …

the cost/hassle of wiring the cost/hassle of wiring

The largest constraint to sharing information is…The largest constraint to sharing information is… data incompatibility data incompatibility

Plant & Factory Information hurdlesPlant & Factory Information hurdles

wireless wireless

wireless gateways wireless gateways

• $40/linear ft$40/linear ft• mobilitymobility• downtimedowntime

• protocolsprotocols• speedspeed• network structurenetwork structure


Wireless Network challengesWireless Network challenges

• Reliable information (data) transfer with… - larger amounts of information demanded- more mobile, flexible and greater scalability- networked from different, and more places

• Connectivity to and from high-speed industrial LAN’s - Profibus (12Mbit/s),DeviceNet (500kbit/s), Modbus (1Mbit/s), Ethernet (10/100Mbit/s)- Interconnectivity to different LAN’s - protocol incompatibility

• Security (process as well as business side of things )- hackers, competitors and other perpetrators- jamming or unwanted messages into process- “malicious” damage?- e.g. disgruntled employees


SMART Wireless Gatewaysoffer…

• Advances on traditional modem

• Protocol conversion - adds flexibility

• Faster by using efficient wireless protocol

• Better network bandwidth management

• Reliable and secure data transfer


““Smart” Radio Modem Smart” Radio Modem

Data bus

Gateways can act as “smart” radio modems to overcome limitations of normal radio modems

Data bus

Data bus

Data protocol only on data bus sideData is converted to a highly efficient wireless protocol on the radio side

The Smart Gateway can now yield tremendous benefit to the User…

SmartGatewa

y

SmartGatewa

y

SmartGatewa

y


LAN Speed ProblemLAN Speed Problem

Conventional Radio ModemsNormal radio modems handle data protocols at 9600bit/s, 19.2kbit/s, etc – slow in today’s information-hungry, high-speed environment

RadioModem

RadioModem

--- data bus speed must be reduced to match the speed of the radio modem, affecting the pre-existing bus ---


LAN Speed SolutionLAN Speed Solution

Wireless Gateways

Wireless Gateways connect to the LAN at full bus data rate

Existing LAN devices are not affected.

profibus – 12Mbit/s

Modbus – 1Mbit/s

Ethernet – 10/100Mbit/s

Transfer at protocol speed

profibus – 12Mbit/s

Modbus – 1Mbit/s

Ethernet – 10/100Mbit/s

wireless


Response Time ProblemsResponse Time Problems

ConventionalConventionalRadio ModemRadio Modem

High speed data protocols require fast response - Profibus (11Mbit/s), DeviceNet (1Mbit/s) etc

RadioModem

RadioModem

Master sends a command to the slave - the radio delays the command

Slave responds, but too late

Master device times out and comms stops

X


Wireless GatewayWireless Gateway

Master sends a command - the Gateway responds, the Master does not time out

The SMART Gateway transmits the information - fast response is maintained by exception reporting wireless protocol

The second SMART Gateway passes on the information:

Communications is successful and continues

A newer approachA newer approach


Network Structure ConstraintsNetwork Structure Constraints

Conventional Radio ModemsConventional Radio Modems

The Wireless Network has the same network structure limitations as the Host protocol - most are master-slave polling networks

RadioModem

RadioModem

RadioModem

RadioModem


Wireless network is independent of the data protocol - peer to peer• Multiple masters - no problems

• Slave to slave - easy add

• Path routing – flexible & quick

Network Structure ImprovementNetwork Structure Improvement

User Scalability & flexibilityUser Scalability & flexibility


Network Bandwidth ManagementNetwork Bandwidth Management

Conventional Radio Modems

Master-slave polling networks become slow as the network size increases

Radio network becomes busy as size increases

RadioModem

RadioModem

RadioModem

RadioModem


SMART Wireless Gateways

Gateways use a more intelligent wireless protocol Based on exception reporting (transmitting on a change), plus transfers on demand

Better Bandwidth ManagementBetter Bandwidth Management


Protocol IncompatibilityProtocol Incompatibility

Modbus

Modbus

DF1

Data bus interconnectivity

Normal radio modems can only connect the same protocol

Profibus

x

x

x

x

RadioModem

RadioModem

RadioModem

RadioModem


Data bus interconnectivity

SMART Gateways use a “neutral” wireless protocol - different data buses can be interconnected

Modbus

Modbus

DF1

Profibus

Protocol CompatibilityProtocol Compatibility


SECURITY

Can Wireless Gateways help against:

• hackers, competitors and other perpetrators• jamming or unwanted messages into process• “malicious” damage?- e.g. disgruntled employees


SecuritySecurity

Data bus

Conventional Radio Modems

• Security achieved by data encryption.

• Unable to limit transfer of data or authenticate the transfer.

Data bus

Data bus

Any data can be transferred

RadioModem

RadioModem

RadioModem


Data bus

SMART Wireless Gateways

Gateways can only transfer known data • Firewall protection to level “7”• Blacklist/white list• AES encryption routine

Data bus

Data bus

Only known approved data can be transferred

SecuritySecurity


Example - Tank Gauging Example - Tank Gauging Profibus

Ethernet

Profibus

Profibus


Example - Tank Gauging Example - Tank Gauging Profibus

Ethernet

Add a High Level Switch

Most Gateways have capability for connection of discrete, analog, and pulse I/O

High level switch

High level switch

High level switch


Profibus

Ethernet

Profibus

Profibus

High level switch

High level switch

High level switch

Devicenet

Modbus + Internet

““Wireless Information Backbone” Wireless Information Backbone”


SummarySummaryWireless Gateway = Smart Radio Modem

Overcomes speed limitations with fast data protocols Allows connection at full bus speed Provides peer-to-peer networking for scalability / flexibility Better wireless network bandwidth management Secure data bus expansion – encryption & firewall Data bus interconnectivity - protocol conversion Internet connectivity - web enabled interface Allows formation of Wireless Information Backbone


Thank you Thank you

Frank WilliamsFrank [email protected] – office858.349.1346 – cell

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Smart Wireless Gateways

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