Latency Testing In The USAF Distributed Mission Operations Environment

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Latency Testing In The USAF Distributed Mission
Operations Environment

• Jerry Szulinski
• LMC Principal Systems Engineer
• Phone [phone]
• Email jerry.szulinski_at_kirtland.af.mil

Chad Simpkins LMC Software Engineer Phone
505-853-1536 Email chad.g.simpkins_at_lmco
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Agenda

• Mission
• DIS Filter overview
• Test bed configuration
• DIS Filter latency study results
• TACCSF Software Router (TSR) overview
• TSR latency test results
• Conclusions
• Future work
• Related papers

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Mission

• Determine the additional DMO network latency due
  to the DIS Filter and the TSR
• Determine the total typical packet transport time
  in DMO

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DIS Filter Overview

• Application software
• Government owned (GOTS)
• Hosted on LINUX
• High performance
• Easy remote access
• Filtering device for simulation data between DIS
  LANs
• Provides sender-based filtering to reduce
  bandwidth
• Provides receiver-based filtering to reduce load
  on simulations
• Data conversion
• Link-16 formats, DIS versions, etc.
• Teleport
• Bandwidth and PDU statistics
• Logging

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Notional Network Design
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DMOC Network Connections
ARCNET
JDEP Net
Seattle(Boeing)
Battle Creek
JTEN
MDANet
Bradley, CT
Ft. Dodge
Offutt AFB (RJMT)
DTOC
WPAFB
Fallon
Pentagon (CVC)
JNTF JNIC (SWC)
Hill AFB
Damneck
St. Louis (CIDS/VWC)
Langley AFB
JFCOM (JTASC)
Nellis (CAOC-N)
Charleston AFB
Tinker AFB
CWIC
DMOC
NTC
29th Palms
DMON CAF DMO
Ft Sill
Luke
TTGP
58SOW
T-1
AFRL Mesa
Robins AFB
Ft Benning
MDANet
Ft. Huachuca
19 SOS
Greenville
DMON
505 CCW
Ft Bliss
Tyndall AFB
Ft Hood
Eglin AFB
JDEP Net
IWC
DMON NOC Orlando, FL
DREN
DREN
ARCNET (CASNET)
JTEN (JNTC)
Not all cloud nodes shown!
As of 14 Jun 04
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Bubble filtering
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Test Bed Configuration

• Sender
• 100 Hz
• Feed steady stream of ES PDUs into the network
• Repeater
• Return the received PDUs ASAP
• Receiver
• Receive the PDUs
• Calculate round trip time
• Log result
• 2.8 GHz 1GB RAM PC
• Red Hat Enterprise Linux 4
• Cisco 3550-48 Fast Ethernet switches
• 100 Mbps mode

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Test Bed Configuration

• Round trip time measured to avoid synchronization
  issues
• 1.676 µs DIS PDU Timestamp resolution
• gettimeofday() system call used for timing
• Five runs per configuration
• 500, 1000, 1500, 2000, 2500 PDUs/sec
• Test duration 65,000 PDUs

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Baseline Test
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DIS Filter Pass-Through Test
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DIS Filter _at_ 50 Filtering Test
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DIS Filter Multiple LANs Test
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TSR Overview

• Network gateway function
• Universal UDP wrapper/converter
• Multicast
• Broadcast
• Unicast
• Uses multiple local interfaces to collect UDP
  packets
• Uses bridging interface to talk to all other
  TSRs
• Re-distribute data at the remote locations

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TSR Overview
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TSR Latency Test
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Conclusions

• Limiting the PDU count reduces latency of the
  remaining PDUs
• Overhead of just having the DIS Filter lt0.5
  msec
• Most latency occurs in network servicing of
  packets not in processing them
• Most common usage of the DIS Filter has
  relatively low impact on system latency
  approximately 0.7 msec _at_ 1000 PDUs/sec

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Future Work

• Test latency across different DMO networks
• DMON, T-1s, DREN, JTEN, MDANet, JDEP, etc.
• Test various hardware devices
• NICs, hubs, switches, bridges, cryptos, etc.
• Provide permanent non-interference latency status
  capability during exercise execution
• Test with actual Virtual Flag loads
• Determine how much latency is too much

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Related Papers

• 05F-SIW-105 Bandwidth Reduction Techniques An
  Update
• 05F-SIW-106 Live, Virtual, and Constructive
  Asset Merge for Joint Red Flag
• 04S-SIW-077 Bandwidth Reduction Techniques Used
  In DIS Exercises

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Questions
MISSION REHEARSAL
SCHEDULING
INTEGRATION
DISTRIBUTED MISSION OPERATIONS
EXPERIMENT
TRAIN
REPOSITORY
SCENARIOS
TEST
RANGE INTEGRATION
DECISION SUPPORT
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