Test1 CCA Preamble Detect Murphy v2.ppt
Transcript of Test1 CCA Preamble Detect Murphy v2.ppt
WISEWiTS Intensive Studies Extension
CCA Preamble Detect Behavior Test
� Test Lukaszewski theory:
– “CCA Preamble Detect: Fact vs. Fiction”
� Sept. 27th, 2015
� Chuck Lukaszewski
� Conduct empirical testing using lab setup
suggested in Chuck’s message
� Post initial results to email group
Objectives
Comments
� This shows the preliminary results of tests
conducted on Oct. 19, 2015 at personal
residence.
� Further tests at a second location are
planned.
Following are the specifications for the Access Point equipment used during this set of tests.
AP51 is a Cisco 1142 (2x3) dual-band 802.11n capable access point.– Autonomous
– Max Rate – 300 Mbps
– ESSID: AP51_Silver
– BSSID: 10:8C:CF:EA:87:70
AP52 is a Cisco 1142 (2x3) dual-band 802.11n capable access point.– Autonomous
– Max Rate – 300 Mbps
– ESSID: AP52_Silver
– BSSID: 10:8C:CF:EA:8D:50
http://www.cisco.com/c/en/us/products/collateral/wireless/aironet-1130-ag-series/datasheet_c78-502793.html
Section 2 - Identifying WiFi Problems 4
802.11ac – VHT Extended ChannelsAP STA Equipment
These are the specifications for the Client STA equipment used during this set of tests.
Wireless Client STA1 - 2013 Apple MacBook Pro Retina 802.11ac 3x3
– Associated to AP52
– Open System/No Encryption
– OS X Yosemite v10.10.1
– Broadcom BCM43xx A/G/N/Ac dual-band (3x3)
– Max Rate - 1300 Mbps
Wireless Client STA2 – AlienWare M17x10
– Associated to AP52
– Open System/No Encryption
– Windows 7 Ultimate / SP1 / 64 bit
– Intel Centrino Ultimate-N 6300 A/G/N dual-band (3x3)
– Max Rate – 450 Mbps
Wired iPerf Server STA3 – Fluke OptiView XG v13.0.0
– Directly connected to 1 Gbps Ethernet backbone
– Windows 7 Professional / SP1 / 64 bit
– Intel Core Duo CPU
– Max Rate – 1 Gbps
Monitor Station STA4 – Lenovo X220 Tablet PC
– AirMagnet Wi-Fi Analyzer v10.7.1 (Bld 35396)
– Windows 7 Professional / SP1 / 64 bit
– Intel Core i7 CPU
– Capture adapter: Proxim 8494-US (Orinoco 802.11 a/b/g/n)
Section 2 - Identifying WiFi Problems 5
802.11ac – VHT Extended ChannelsClient STA Equipment
These are the setup specifications used during this set of tests.
Testing Suite– jPerf (iPerf) server mode was used on a wired STA3 (Optiview XG)
– jPerf (iPerf) client mode was used at each Client STA
– AirMagnet Wi-Fi Analyzer was used on STA4 for side-by-side monitoring
Client STA1– Associated to AP1_Silver on 2.4 GHz, Ch 11, RSSI -89 (avg)
Client STA2– Associated to AP2_Silver on 2.4 GHz, Ch 11, RSSI -89 (avg)
RX Antenna Delta – Distance between Monitor STA and Clients– STA4 to STA1 ~5ʎ (24 in.)
– STA4 to STA2 ~5ʎ (24 in.)
Section 2 - Identifying WiFi Problems 6
802.11ac – VHT Extended ChannelsSetup
Begin First Test Procedure
� Connect and test throughput between
AP51 and STA1 only
� Connect and test throughput between
AP52 and STA2 only
STA4 View of AP51
STA1 Only Test Results
Initial Results: Client STA1 Only
� Wireless Client STA1 associated to
AP51_Silver on 2.4 GHz channel 11
– 60 second iPerf test run
– -89 dBm RSSI measured at STA4
– 87 Mbps nominal PHY rate to STA1
– 21.1 Mbps average iPerf throughput rate
(unidirectional)
STA4 View of AP52
STA2 Only Test Results
Initial Results: Client STA2 Only
� Wireless Client STA2 associated to
AP52_Silver on 2.4 GHz channel 11
– 60 second iPerf test run
– -87 dBm RSSI measured at STA4
– 39 Mbps nominal PHY rate to STA2
– 13.9 Mbps average iPerf Throughput Rate
(unidirectional)
Begin Second Test Procedure
� Connect and test throughput between
AP51/STA1 concurrent with AP52/STA2
� RSSI of concurrent devices on same
channel < -82 dBm
STA1 and STA2 Concurrent: STA4 View of AP51
STA1 and STA2 Concurrent: - STA2 begins test at 60 secs. -
STA1 and STA2 Concurrent: - STA1 test average at 300 secs. -
Initial Results: STA1 and STA2 Concurrent
� Wireless Client STA1 associated to
AP51_Silver on 2.4 GHz channel 11
– 300 second iPerf test run
– -86 dBm RSSI measured at STA4
– First 60 seconds, 14-15 Mbps average iPerf
Throughput Rate (unidirectional)
– At 61 seconds drops to 1-4 Mbps as STA2
begins testing
– Displays moderate to high jitter
– STA1 final average 5.57 Mbps
STA1 and STA2 Concurrent: STA4 View of AP52
STA1 and STA2 Concurrent: - STA2 begins test — STA1 already active. -
STA1 and STA2 Concurrent: - STA2 testing as STA2 ends -
STA1 and STA2 Concurrent: - STA2 throughput after STA1 ends. -
STA1 and STA2 Concurrent: - STA2 test average at 300 secs. -
Initial Results: STA1 and STA2 Concurrent
� Wireless Client STA2 associated to AP52_Silver
on 2.4 GHz channel 11
– 300 second iPerf test run
– -87 dBm RSSI measured at STA4
– First 240 seconds, 2-3 Mbps average iPerf
Throughput Rate (unidirectional)
– Displays moderate to high jitter
– At 243 seconds speed jumps up as STA1 completes
testing
– STA2 throughput speed 20 – 25 Mbps at 299 seconds
– STA2 final average 6.6 Mbps
Chuck Lukaszewski wrote:
“I would love to be wrong about this, but…”
� At this time, these results cannot dispute Chuck’s suggestion.
� However, additional tests will be performed using a different
location, different vendor equipment, 802.11ac capable equipment,
and 5 GHz channels.
� I will also attempt to use an even lower RSSI, somewhere closer to -
90 dBm
� I would like to know if anyone else has attempted these tests and
what their observations were.– Rick
– Mobile – 303-246-4257
Initial Determination