03SSIW112 Open, MessageBased RTI Implementation A Better, Faster, Cheaper Alternative to Proprietary

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03S-SIW-112Open, Message-Based RTI
Implementation - A Better, Faster, Cheaper
Alternative to Proprietary, API-Based RTIs?
General Dynamics Kevin Mullally Gary
Hall Blue Sky Computer Systems Don Gordon PEO
STRI Barbara Pemberton Chuck Peabody
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Topics

• Discuss Rationale for RTI Alternatives
• Present MessageBased RTI Implementation
• Make recommendations for future development

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Project Scope of Concern
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Current Project

• Intelligence and Electronic Warfare Tactical
  Proficiency Trainer (IEWTPT)
• Requirements
• 25,000 Real-time Entities
• Up to 90 Federates
• 24 Hour Exercise With Low Failure Rate
• Recover From Failure Within 15 Minutes
• Maintain System for 10 Years
• Embedded Simulations on Intelligence Systems
• Wireless Connection to Some Federates
• Managing risk based on history using DMSO RTI

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Risk Management for HLA RTI
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API-Based versus Message-Based RTI
API-Based
Message-Based
Standard API to Third Party RTI
Standard Message Formats and RTI Service
Algorithms
Third Party Software
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Proprietary vs. Non-Proprietary Approach
API-Based
Message-Based
Proprietary
Open

• Difficult to troubleshoot tightly coupled
  proprietary software

• Open protocol allows federates to own and
  maintain RTI software

• Performance improvements are difficult with
  narrow visibility

• Improvements are planned and measured in the open

• RTI vendors are on different development paths

• Community involvement drives technology where it
  is needed

• Benefit of COTS RTI is reuse. Software only
  developed once

• Opportunity for reuse of source code and COTS
  solutions.

• Updates depend on the discretion and schedule of
  RTI venders

• Updates in control of federate developers and
  community

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Centralized vs. De-Centralized Control
API-Based
Message-Based

• Central arbiter exhibits control over the entire
  federation (fedex, rtiexec)

• Each federate independently executes RTI services
  according to protocol

• Single point of failure known to bring down the
  entire federation

• Greater reliability with independent operation of
  RTI services

• Difficult to bring a federate back into a
  federation

• Federate simply restarts and begins executing

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RTI Interoperability
Open Message Format
API-Based
Message-Based

• Interoperability is not prevalent between
  different RTI vendor applications and between
  versions from the same RTI vendor.
• Dynamic Link Compatible HLA API PDG is addressing
  the issue of API standardization and RTI
  compatibility.
• Regardless, all federates have to use the same
  RTI.

• There is an inherent level of federate
  interoperability.
• Issues of compatibility between different
  versions of the message protocol can be handled
  in an open forum.

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Embedded Simulation

• Future transformation requires Embedded
  Simulations
• Embedded RTI must
• Work on any platform (Micro-controller, Firmware,
  DOS)
• Allow developer to scale down and optimize for
• Memory Utilization
• Processor Utilization
• Network Bandwidth (Wireless)
• Power Consumption
• Account for Reliability Issues
• Breaks in Network Connectivity
• Intermittent Federate Availability

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Future Systems
Wireless
Message-Based RTI
Bridge
API-Based RTI

• Embedded Simulations working with Message-Based
  RTI
• Message-Based RTI maintaining interoperability
  with API Standard

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Message-Based RTI Protocol (DRAFT)

• Current Capability
• Creation and Deletion of a Federation Execution
• Creation and Deletion of Objects
• Update of Object Instance Attributes
• Initiation of Interactions
• Future Research
• Ownership Management
• Time Management
• Data Distribution Management

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Message-Based RTI Protocol (DRAFT)HLA 1.3
Interface Services Supported
RTI Ambassador Services
Federation Management createFederationExecution de
stroyFederationExecution joinFederationExecution r
esignFederationExecution
Ancillary Services getAttributeHandle getAttribute
Name getInteractionClassHandle getInteractionClass
Name getObjectClass getObjectClassHandle getObject
ClassName getObjectInstanceHandle getObjectInstanc
eName getParameterHandle getParameterName Tick
Object Management deleteObjectInstance localDelete
ObjectInstance registerObjectInstance requestClass
AttributeValueUpdate requestObjectAttributeValueUp
date sendInteraction updateAttributeValues
Declaration Management publishInteractionClass pub
lishObjectClass subscribeInteractionClass subscrib
eObjectClassAttributes unpublishInteractionClass u
npublishObjectClass unsubscribeInteractionClass un
subscribeObjectClass
Federate Ambassador Services
Object Management discoverObjectInstance provideAt
tributeValueUpdate receiveInteraction reflectAttri
buteValues removeObjectInstance
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Message-Based RTI Protocol (DRAFT) Example
Message
Bundle Header
1st Message Header
1st Message
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Performance Comparison

• Side by Side Comparison
• DMSO RTI 1.3NGV6
• No Time Management
• No DDM
• No MOM
• Message-Based RTI
• HLA Direct
• Network Interface Plug-in
• Tested for 1, 5, 10, 15, 20 thousand objects
• Used Microsoft Performance tool

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Object Creation and Deletion Time
DMSO RTI 1.3NGV6
DMSO RTI 1.3NGV6
Message-Based RTI
Message-Based RTI
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CPU Memory Utilization
DMSO RTI 1.3 NG V6
DMSO RTI 1.3 NG V6
Message-Based RTI
Message-Based RTI

• Data measured during Object Updates

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Network Bandwidth Update Rate
DMSO RTI 1.3 NG V6
DMSO RTI 1.3 NG V6
Message-Based RTI
Message-Based RTI

• Data measured during Object Updates

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Risk Management Review
Good Performance
Scalable
Federates Have Ownership Of Source Code
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Summary

• Identified need for RTI alternatives
• Presented Message-Based RTI Implementation as a
  viable alternative
• More Developer Control
• Low Maintenance Costs
• Strong Reliability
• Good Performance
• High Level of Interoperability
• Good Fit for Future Embedded Simulations
• Offering Message-Based RTI Protocol (DRAFT) as a
  starting point

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Recommendations

• Propose Study Group for Message-Based RTI
  Protocol
• Solicit interest as a community standard
• Collaborate on improvement of protocol

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Contact Information

• For copy of Message-Based RTI Protocol (DRAFT) or
  more information, contact
• Gary Hall Gary.Hall_at_gdds.com
• Kevin Mullally Kevin.Mullally_at_gdds.com
• General Dynamics Decision Systems
• [phone]