The document summarizes a presentation about measuring and monitoring network performance in school districts across Georgia. It discusses how the Georgia Measurement and Monitoring (GAMMON) project collects quantitative data on network usage and application performance. This data helps identify bandwidth limitations that impact education technology use in classrooms. GAMMON also analyzes how districts' network capacities align with their technology plans and provides recommendations on improving performance.

1. What Everyone Needs to Know About Network Performance
Warren Matthews, PhD
Research Scientist II
Office of Information Technology
warren.matthews@oit.gatech.edu
Lisa Flynn, EdS
Chemistry and Technology Integration
Osborne High School, Cobb County Schools
lisa.flynn@cobbk12.org
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2. Abstract
• We will present quantitative data of network
performance from school districts around
Georgia, and describe the limitations it sets
for the performance of education applications
in the classroom. The measurements will also
be put in perspective by examining the
districts own technology plan. The session is
suitable for both IT support staff and teachers
interested in the use of technology to enhance
their classes.
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3. Funding
GAMMON is funded in part by
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4. What Everyone Needs to Know About Network Performance.
PART 1: WHAT AND WHY?
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5. What is GAMMON?
• The Georgia Measurement and Monitoring
(GAMMON) project gathers quantitative
data about network and application
performance.
– Troubleshooting, Planning
(analytics, business
intelligence), Security, Inventory.
– Provide the quantitative evidence to back-up
qualitative experiences.
• Since 2006, revitalized in 2011.
If you don’t measure, you don’t
know. (Kevin Walsh, UCSD)
Measure, measure, measure.
(Rico Mariani, Microsoft)
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6. Active Measurements
Active measurements inject additional
traffic onto the network to determine endto-end performance across the Internet.
GAMMON
Server
GAMMON
Server
Internet
GAMMON
Server
GAMMON servers are placed at
the edge of the school district
network, making tests and
measuring performance across the
Internet between each other.
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7. Passive Monitoring
Internet
Core
Switch
GAMMON
Server
ES
Passive monitoring is peeking at
real traffic as it goes by, not adding
to the traffic on the network.
MS
HS
GAMMON servers can gather
data as they enter and leave the
district.
Admin
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8. Why?
• Network demand in the classroom has
quadrupled over the last five years.
• In a 2010 Federal Communications
Commissions survey of E-rate connected
schools, nearly 80% of respondents
reported that they had inadequate
bandwidth to meet educational needs.
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9. 9

10. 10

11. Direct-To-Discovery
GT Professor Lisa
Yaszek leading a
book discussion
between GT class
and middle school
kids in Barrow
County.
GT Professor Jim
Sowell leading an
astronomy lesson
with classroom in
Australia.
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12. Application Performance
Not interactive
Highly interactive
HD video conferencing
Gaming Telephone call
Web surfing
Email
• High bandwidth
• Low latency
• Low jitter
• Low bandwidth
• Latency and
jitter are almost
unimportant
When you’ve
got to get to the
Airport.
When you’re
out for a Sunday
Drive.
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13. Motivation (1/2).
• Is it feasible to expect schools to do more
and more online?
– Governor’s Digital Education Task Force.
• “I learned with paper and pencil. Today’s
students learn with light” (Anonymous).
– But many school districts in Georgia
experience slow downloads, choppy audio and
video. Access points are maxed out. Online
resources too have downtime.
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14. Motivation (2/2).
• Teachers are expected to teach bell-tobell, but they can’t if they’re waiting for the
technology. Many report that this is the
rule, not the exception.
– Our assumption is this disrupts online
learning.
• Not surprisingly, districts want to know
what is going on in their network.
– but report that they are blind, or partially
blind.
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15. Why develop more tools?
• Varying levels of hardware and software to
monitor traffic.
• Do not reinvent the wheel, but
– Common platform to compare results.
– Cost of GAMMON vs numerous commercial
tools.
– Extra pair of eyes.
– Share the philosophy of research.
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16. What Everyone Needs to Know About Network Performance.
PART 2: HISTORY AND
BACKGROUND
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17. Can we be Friends?
• Similarities with the research community
– Bandwidth is required but not sufficient.
– Development of Research networks (15-20
years ago)
• Research and education are birds of a
feather.
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18. perfSONAR
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19. Capacity
• Is it enough?
– Now?
– Next month?
– Next Year?
– How do you know?
• What do the school
districts plan to do
with online
learning?
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20. Current Deployment.
Currently there are 18 GAMMON
servers deployed around Georgia.
Each server measures the one-way
delay and route to all the others.
Data is being gathered but analysis and
interpretation is required.
The current servers are mostly reused
machines from older projects.
GAMMON itself grew out of CPR, an oncampus measurement project.
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21. Problem.
Round Trip Time
This graph show the round trip time (in milliseconds) between the clean room
at Georgia Tech and a school district central office . We look “under the hood”
and see what causes the slow downloads, choppy audio and video. Think about
the time it takes to drive through Atlanta at different times of the day.
Day of the month
In the evenings and weekends, delay is
5 milliseconds, just like driving on I-85.
Severely congested connections
mean long delays, just like driving on
I-85.
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22. Round Trip Time
Solution.
2.4 milliseconds
2.2 milliseconds
Day of the month
This graph show the delay (in milliseconds) between the clean room at
Georgia Tech and a school district central office .
Compare to the problem graph –
good connectivity is like your own
private Peach Pass.
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23. Example of an Upgrade.
Barrow County School System upgraded from 20 Mbps to 150 Mbps.
Immediately see usage 23x previous capacity.
More capacity means less congestion. Less Congestion enables interactive applications.
Interactive Applications enhance learning, especially when combined with the right
teacher and the right opportunities.
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24. Putnam County Schools
"GAMMON greatly helped me sell the need for bandwidth
to my school board.”
-Keith Ellenberg, Chief Operating Officer,
Putnam County Charter School System
300
250
200
Capacity (Mbps)
150
100
50
0
2007
2008
2009
2010
2011
2012
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25. What Everyone Needs to Know About Network Performance.
PART 3: MEASUREMENTS
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26. Achievable Bandwidth
Preliminary
Preliminary
*
Barrow, Ware, Gilmer, Sumter, Clarke, Dawson, White, a
nd Rabun have multiple providers.
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27. Achievable Bandwidth Per
Student
• The only good
network is one that
is not a bottleneck.
• Measurements will
be put into context.
Preliminary
Another view is under development.
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28. Smokeping
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29. Network Map
Might replace MRTG with Cacti.
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30. Hosts
Hosts seen by school.
Last 5 minutes.
Last Hour.
Yesterday.
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31. NMAP
• Create a database of
ports
– Track services
– Detect Changes
• Evaluate free tools
– Intrusion detection
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32. Total Traffic by Protocol
Evaluating plugin to monitor SYN and RST packets
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33. Traffic by Application
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34. Traffic by Destination
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35. Pythia
• Pythia uses GAMMON measurements to
detect and diagnose network problems.
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36. More Tools
• Work in Progress
• Verify Content Filters
• More External measurement
– PAM tools
• More Internal measurements
• More netflow analytics
– SYN Flood
• Routing (especially multi-homed).
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37. Join the Website
• https://gammon.gatech.edu
• Not much to see yet.
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38. What Everyone Needs to Know About Network Performance.
PART 4: WHAT DOES IT
ALL MEAN?
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39. Summary
• GAMMON quantified network performance
– Provides decision makers with data based
information to improve network performance
– improves network utilization in the classroom
decreasing loss of valuable educational time
• Limitations are identified using the data
which are impeding the performance of
educational applications and media in the
classroom.
• Work in Progress
– Catch up at GAMEIS or GAETC next year.

40. Conclusions and Recommendations
• Even with a small sample, variation in
performance and philosophy is huge.
• Many districts suffer congestion.
– No surprises but graphs to prove it.
– We assume this impacts learning.
• How much is enough?
– External bottlenecks -> internal bottlenecks.
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41. This year (2013-2014)
• More measurements, More analysis
– Readiness Index
– District’s Technology Plans
• Summer 2014
– Performance workshop and GAMMON training.
– Secure K-12 workshop
• We hope to have funding to increase
deployment next year
– What if you can’t wait?
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42. How to get involved
• Let us know you’re interested.
• Join the monthly conference call.
• Install your own server
– We can provide specs
– Install software, Provide access for us to analyze.
• Create account on website.
– Allow us to share information amongst the
community.
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43. Contact Us.
• For more information, please contact
Warren Matthews
– warren.matthews@oit.gatech.edu
– 678-992-9185
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44. Thanks
• Bill Price and GTA
• Bob Swiggum, Rep. Mike
Dudgeon, Joseph Barrow.
• Annette, Gino, Leon, Suren
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45. Thanks
• And especially all the sites that host
servers, and the people that got them there.
– John St.Clair, Morad El-Jourbagy, Jeremy
Caswell, Terry Treadgill, Phil Kline, Keith
Ellenberg, Sam Ganas, Carol Helton, Jodi
Perdue, William Sperin, Chris Usrey, John
Call, Jefferey Harrel, Twanda Banks, Charlie
Coleman, Aubrey Jones, David Smith, Taylor
Duke, Tim Maynard.
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46. What Everyone Needs to Know About Network Performance.
ANY QUESTIONS?
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