Post on 24-Apr-2015
description
Standards
Certification
Education & Training
Publishing
Conferences & Exhibits
Solving the Issue of Interoperability among Devices and Systems
ISA100 Wireless Solutions Summit
19 May 2008
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Presenter
• David D. BrandtPrincipal EngineerRockwell AutomationAdvanced Technology – Milwaukeeddbrandt@ra.rockwell.com
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About the ISA100 Standard Activity
• Multiple protocol support on a single, integrated wireless network (ISA100.11a):– ISA100.11a native– HART®– FOUNDATION™ Fieldbus– PROFIBUS– Modbus®– CIP™– Others
• Multiple radio support in a family of standards (ISA100):– Process Automation (Process Focus)– Factory Automation (Discrete Focus)– Transmission and Distribution (Long Distance Focus) – RTLS/RFID (Industrial Tagging Focus)
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Challenge: How to provideInteroperability among Devices and Systems?
Asset Management Engineering Tools HistoriansControl Systems
Otherapplications
MixedAutomation
Systems
HART®, FOUNDATION™ Fieldbus, PROFIBUS, Modbus®, CIP™, ...
EmbeddedWirelessDevice
WirelessAdapter
WiredDevice
MixedWired andWirelessDevices
ISA100.11a,WirelessHARTTM,
ZigBee®,…
HART®,FOUNDATION™Fieldbus,
PROFIBUS,Modbus®,
CIP™,...
Gateway
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A specific challenge:ISA100.11a / WirelessHART™ Interoperability
• ISA100-WirelessHART Joint Analysis Team (JAT) addressed this issue
• The ISA100.11a draft standard has followed the recommendations for release 1:– Enable dual-mode gateways– Develop a “common high-side interface” in the gateway
– As a common model and interface for mixed systems and devices
– Base the interface on the WirelessHART™ optional XML interface– Specify as an implementation neutral Service Access Point
– Provide enhanced tunneling for application layer protocols
– Provide generic wireless network management that is separate from the application protocols
– Provide information to facilitate coordination of RF usage
• Convergence below the gateway will be considered for later releases
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Multimode Gateway withCommon High-side Interface
ISA100.11a WirelessHART™
ISA100.11a specific interfaces
WirelessHART™specific interfacesISA100.11a Stack
(PHY through APP)
WirelessHART™ Stack
(PHY through APP)
Protocol translator and stack to communicate with plant network of choice
Coe
xist
ence
Fea
ture
s an
d F
unct
ions
OtherStack…
Common High-side Interface“Other”specific interfaces
“Other”e.g., Bluetooth®,
ZigBee®, etc.
Asset Management Engineering Tools HistoriansControl Systems
Otherapplications
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Gateway ServiceAccess Point (GSAP)
• Session• Lease• Messaging
– Publish/subscribe
– Client/server
– Source/sink
– Bulk transfer
• Alert• Reports
– Device List
– Topology, Schedule
– Device Health, Neighbor Health, Network Health
• Time Synchronization• Gateway configuration
This is the Common High-side Interface used by protocol
translators.
This is the Common High-side Interface used by protocol
translators.
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EmbeddedWirelessDevice
WirelessAdapter
WiredDevice
GSAP: Session Service
Asset Management Engineering ToolsControl Systems
ProtocolTranslator
Gat
eway
Session
Protocol translators act on behalf of plant
applications to establish sessions with the gateway entity through the
GSAP session service.
Sessions allow resource allocation for
a specific network.
Resources are reclaimed when a
session ends.
GSAP
Gateway Entity
EmbeddedWirelessDevice
WirelessAdapter
WiredDevice
Translatingproxy
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Gateway Entity
GSAP
Protocol Translator
GSAP: Lease Service
Protocol translators act on behalf of plant applications to
establish leases within sessions to allocate specific
communication resources.
Leases allow dynamic resource allocation and release.
Resources are allocated within the gateway entity, the network,
or both.
Specific types of leases are available for: publish/subscribe, client/server, bulk transfer and
alerts
Control SystemsLease
WirelessAdapter
WiredDevice
Translatingproxy
EmbeddedWirelessDevice
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Buffer
Publish Subscribe Client Server
BulkTransferClient
Subscribe Publish Server Client BulkTransferServer
Buffer
Buffer
Buffer
Buffer
•Change of state delivery•Local caching•Synchronization
Buffer BufferBuffer
•Optional caching
•Large item transfer•Reliable, in-orderdelivery
Alert
Alert
GSAP: Messaging Services
Translatingproxy
Protocol translators act on behalf of plant applications to utilize lease-based messages
services to perform messaging that supports protocol
translation.
Protocol specific application content is carried in the
messages.
Message Services
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Protocol Translator
GSAP: Report Services
Common reports available, independent
of the underlying wireless technology.
GSAP
Gateway EntityReport Generation
CommonReports
Gat
eway
Translatingproxy
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GSAP: Device List Report Service
Protocol translators present each wireless device as if it
were a wired device within the plant network.
The device list report service allows the wireless devices to
be discovered and mapped into the plant network, ultimately
linking to the control strategy.
Each device has a globally unique identifier.
EDDL and other device description methods extensions
can enable linkage without additional tools.
GSAP
Gateway Entity
Protocol Translator
Proxy1
Proxy2
Proxy3
Proxy4
Control SystemPlantNetwork
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Protocol Translator
GSAP: Health Report Services
Health reports are available to alert
control systems to underlying problems in a generic manner.
Health reports are also available to asset management systems
for maintenance purposes.
Protocol translators are responsible for
conversion to specific formats.
GSAP
Gateway Entity
Report Generation
Gat
eway
DeviceHealth
NeighborHealth
NetworkHealth
Translating proxy
Asset ManagementControl Systems
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GSAP: Topology Report Service,Schedule Report Service
Topology and Schedule reports enable the ability to “drill down” when a Health
report indicates a communication problem.
When devices from different types of wireless networks
share the same physical space, channel and
transmission schedule can be evaluated for coexistence
improvement opportunities.Network 1Node 1
Network 1Node 2
Network 2Node 1
Network 1Node 2
Time,Channel
Time,Channel
Errors Errors
Protocol Translator
GSAP
Gateway Entity
Report Generation
Topology Schedule Health
Translating proxy
Engineering Tools
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Protocol Translator
GSAP: Time SynchronizationService
Services are available to synchronize underlying wireless networks to an
external source.
This is useful when the same source is used in a
control system.
This is also useful to synchronize wireless
device communication across wireless networks.
Protocol translators can adapt a variety of sources.
GSAP
Gateway EntityTime Synchronization
Gat
eway
Translatingproxy
Clock Source
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Example wireless deviceintegration scheme
MultipleSystems
Control Systems
A single wireless device (single catalog number) can operate
across multiple systems.
A specific protocol translator is required in
the gateway for each system.
ISA100.11a provides an efficient application
model that native devices can use for this
purpose.
Gat
eway
GSAP
Gateway Entity
Translatingproxy
Control Systems
Translatingproxy
Control Systems
Translatingproxy
HART®Application
FOUNDATION™Fieldbus
Application
PROFIBUSApplication
SingleGenericDevice
MultipleProtocol
Translators
EmbeddedWirelessDevice
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Example wired deviceintegration scheme
MultipleSystems
Control Systems
Wired devices can operate across multiple
systems.
A simple protocol translator is required in the gateway to tunnel
each protocol.
Adapters must also implement the tunnel
protocol.
ISA100.11a provides an efficient tunneling
model that can be used for this purpose.
Gat
eway
GSAP
Gateway Entity
Control Systems Control Systems
HART®Application
FOUNDATION™Fieldbus
Application
PROFIBUSApplication
SingleDevice
TunnelingProtocol
Translators
WirelessAdapter
WiredDevice
Translatingproxy
WirelessAdapter
WiredDevice
WirelessAdapter
WiredDevice
Translatingproxy
Translatingproxy
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Conserving battery life:Minimizing transactions with caching
PlantNetwork
Gateway
Control Systems
Caching reduces transactions
(increasing battery life).
Caching gives immediate
response to application if used
properly.
Both ISA100.11a native messaging
and tunneled messaging utilize cache techniques.
TunneledInformation
NativeInformation
BufferBuffer
Informationis routed throughgateway cache
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Conserving battery life:Reducing header sizes
Address Length DataIntegrityCheck
ApplicationContent
PlantNetworkWiredPacket
Address Length DataIntegrityCheck
WirelessPacket
Address Length DataIntegrityCheck
TunneledDeviceWiredPacket
PlantNetwork
Gateway
WirelessAdapter
WiredDevice
Control Systems
MAP
MAP
CARRY
CARRY
CREATE
CREATE
CREATE
CREATE
Enhanced tunneling reduces the size of packets (increasing battery life) via a “configuration agreement” to map and create fields rather than carrying them.
ISA100.11a native messaging provides numerous mechanisms to reduce header size.
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Benefits to Users
• Protects investment in legacy devices and protocols• Reduces the lifecycle cost associated with gateways
– Acquisition cost (less gateways)– Training and Maintenance cost (common gateway model)
• Provides a future migration path – For wired devices– For improved wireless technology– First step on path to more complete integration with
WirelessHART™, anticipated to be upgradeable to “Release 2” approach without impacting higher level applications
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Benefits to Vendors
• Reduces development cost and time – Design to a common gateway model
– Independent of plant network
– Independent of low-power wireless network
– Single paradigm fits both ISA100 and WirelessHART™ architectures
• Enables value-added integration enhancements– E.g., time synchronization across networks– E.g., coexistance coordination tools