In this webinar Lincoln Lavoie, Senior Engineer, Broadband Technologies, details new and expanded WiFi testing and measurement capabilities being offered at the lab. Robust testing and measurement is key to the continuous improvement of broadband services, and WiFi performance has become critical to that equation.

1. The University of New Hampshire
InterOperability Laboratory
(UNH-IOL)
www.iol.unh.edu
New & Expanded WiFi Test & Measurement
Assures Performance at the Network Edge
#UNHIOL#WiFiwebinar

2. •Wireless at the Network Edge
•Creating a Test Environment
•Testing
o Range, Fairness, Operations, Noise, Interop, Roaming, Mesh
•Industry Directions
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Agenda

3. Nearly all edge network access utilizes a wireless
technology, making the wireless a key driver in the user’s
quality of experience (QoE)
QoE is the user’s perception of the network performance
Poor wireless performance à Poor QoE
Poor QoE à User complaints
3
Wireless at the Edge

4. •Challenge:
o Service providers must improve the QoE for risk loosing
customers
•Solutions:
o Provide customers with well known (tried & tested) solutions
o Cooperate with manufacturers to test WiFi equipment before
field deployment
§ Repeatable testing to easily set baselines and find deviations caused by software or
hardware changes
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Wireless at the Edge

5. •A typical broadband home
o 4 Family Members
o 1 Access Point
o 1 laptop
o 4 Smart Phones
o 2 tablets
o 2 TVs (w/ media player)
•This list is growing
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Wireless at the Edge

6. •Generations of technology
o IEEE 802.11a/g
o IEEE 802.11n
o IEEE 802.11ac Wave 1
o IEEE 802.11ac Wave 2
•Access Point technology dominates performance setting
o Wave 2 AP out performs a/g AP
o Maximum performance when all stations match AP
capabilities
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Wireless at the Edge

7. •Performance Impactors
o AP Location (range)
o Number of stations (fairness)
o Other wireless systems (noise)
o Network changes/association/beacons (operations)
o Other device types (interoperability)
•Predicting QoE
o Testing for the above categories can ensure deployed
equipment will perform adequately to prevent low QoE scores
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Wireless at the Edge

8. •UNH-IOL performance testing
environment building upon
octoScope octoBox personal test
bed
•Addresses testing for the 4 key
categories: range, noise,
operational, interoperability
o Additional Testing: roaming, mesh
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Creating a Test Environment

9. •Control
o One variable under test
•Repeatability
o Low noise
o Automation capabilities
•Flexibility / Future Proof
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Creating a Test Environment
•Cabled path between
DUT and partner(s)
•Controlled path using
attenuators and channel
emulator
•Chambers eliminate
external noise sources
•Support for 4 spatial
streams, future up to 8
•Nearfield antenna simplify
test setup

10. 10
Creating a test Environment
•Isolation Chambers
o Turntable
o Nearfield antennas
•MPE2 – Multi-path emulator
•Attenuator(s)
•PAL Partner Device(s)
•Noise Generator

11. • Controlled channel between two devices
(DUT & Partner)
o Partner can be real device or emulated
endpoint
• Multi-path emulator and Quad-Attenuator
create the “distance” between AP / Station
• Measure total throughput between DUT and
Partner
• DUT is rotated to ensure uniform spatial
performance
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Testing: Range

12. •Test results indicate
performance:
o Bit-rate / Throughput
o Latency
•Test setup / design ensures
repeatability
o Can be used to set absolute
performance requirement
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Testing: Range
0
20
40
60
80
100
120
140
160
0 10 20 30 40 50 60
Throughput (Mbps)
Attenuation (dB)
Throughput vs. Range in the 2.4 GHz
Band (Downstream)
0 deg
90 deg
180 deg
270 deg
Avg. Baseline
0
20
40
60
80
100
120
140
160
0 10 20 30 40 50 60
Throughput (Mbps)
Attenuation (dB)
Average Throughput vs. Range
in the 2.4 GHz Band
Downstream
Upstream

13. • Test for AP device under load from multiple stations
o Pre-Wave2 devices can not talk in multiple directions
• Emulated stations perform simultaneous throughput
measurements
o Can be mix of technologies (e.g. 802.11g and 802.11n)
• Ideally, all stations granted similar access to “airtime”
resulting in similar performance
o Can be used to verify functionality provided by QoS functions
(Wi-Fi Alliance WMM for example)
o Complex cases vary the “distance” (power) to from each
station
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Testing: Fairness

14. •Test for AP device under stress
from other operations:
o Association / Authentication /
Disassociation
o Mixed Stations (802.11 standard)
o Mixed Data Rates (fixed MCS)
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Testing: Operations

15. •Test for AP or Station operating
under noise environment
•Noise sources include:
o Other 802.11 systems
o Other technologies: Bluetooth,
Zigbee, etc.
o External Sources: Microwave
Oven, etc.
o Regional Sources: Radar
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Testing: Noise

16. •Key use cases when Dynamic Frequency / Channel
selection is enabled.
o AP / Station adjust to avoid interference or congested
channels
o Can measure adjustment / convergence timing or
performance impact(s)
•Radar avoidance is mandatory feature from 802.11
specification
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Testing: Noise

17. 17
Testing: Interop
•Verify performance against a
variety of common devices (AP
or Station)
o Typical test partners
(AP):Netgear N7500 &
Nighthwak, Linksys 2600;
(Stations): iPhone, iPad, Apple
TV, Google Pixel, Chromecast

18. •Test station transitions
between multiple AP
o Can be used with and without
active control (i.e. enterprise
applications)
•New applications enabling AP
to AP communication optimize
station transition / associations
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Testing: Roaming

19. •Similar to roaming testing, but
with Wireless only path
between APs
•Becoming increasingly
important with multi-AP
solutions
o Cross vendor solutions on the
horizon
19
Testing: Mesh

20. •Service Provider Challenge:
o Improving customer QoE with better WiFi
•Answer: Broadband Forum Test Plan
o First industry accepted performance test plan
o Stated 2017, expected to complete (publish) during 2018
o Considerations given for repeatable testing, with performance
requirements
§ Service providers can use the test plan and results to evaluate potential equipment
(levels the playing field)
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Industry Directions

21. •UNH-IOL is continuing to augment test plans
o Available to UNH-IOL member companies
o Testing tends to lead ahead of standardized testing
•Strong partnerships with T&M equipment provides
ensures cutting edge testing
•On our roadmap:
o Range testing with fine-gain rotation
o Additional fairness testing
o Receiver/stress testing
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Industry Directions

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#UNHIOL#WiFiwebinar

23. •Lincoln Lavoie
o UNH-IOL Senior Engineer, Broadband Technologies
o lylavoie@iol.unh.edu
•UNH-IOL WiFi Testing Services:
o https://www.iol.unh.edu/testing/mobile/wifi
•octoScope Test Equipment:
o https://www.octoscope.com/
•Broadband Forum Test Plan:
o https://issues.broadband-forum.org/browse/CONTRIB-20265
(draft, members only)
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References & Contacts