strobe actively securing wireless communications using zero-forcing beamforming narendra anand rice...
TRANSCRIPT
![Page 1: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/1.jpg)
STROBEActively Securing Wireless Communications
using Zero-Forcing Beamforming
Narendra AnandRice University
Sung-Ju LeeHP Labs
Edward KnightlyRice University
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Motivation
Indoors (eg. Coffee Shop)
AP
![Page 3: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/3.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
AP
![Page 4: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/4.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
![Page 5: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/5.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
![Page 6: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/6.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP WEP/WPA
![Page 7: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/7.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
Omnidirectional
WEP/WPA
![Page 8: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/8.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
Omnidirectional
WEP/WPA
![Page 9: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/9.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
Omnidirectional
WEP/WPA
![Page 10: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/10.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
Omnidirectional
WEP/WPA
Problem:Omnidirectional Transmissions
broadcast signal energy everywhere allowing any user in range to overhear
the transmission.
![Page 11: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/11.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
![Page 12: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/12.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
Potential Solution:Keep signal away from E withSingle-User Beamforming orDirectional Antenna
![Page 13: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/13.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
Potential Solution:Keep signal away from E withSingle-User Beamforming orDirectional Antenna
![Page 14: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/14.jpg)
Motivation
Indoors (eg. Coffee Shop)
IU
E
EAP
Potential Solution:Keep signal away from E withSingle-User Beamforming orDirectional Antenna
**Beampatterns for Illustration purposes only.
![Page 15: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/15.jpg)
E
Motivation
Indoors (eg. Coffee Shop)
IU
E
AP
Potential Solution:Keep signal away from E withSingle-User Beamforming orDirectional Antenna
LOS
**Beampatterns for Illustration purposes only.
![Page 16: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/16.jpg)
E
Motivation
Indoors (eg. Coffee Shop)
IU
E
AP
Potential Solution:Keep signal away from E withSingle-User Beamforming orDirectional Antenna Multi-Path
LOS
**Beampatterns for Illustration purposes only.
![Page 17: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/17.jpg)
E
Motivation
Indoors (eg. Coffee Shop)
IU
E
AP
Potential Solution:Keep signal away from E withSingle-User Beamforming orDirectional Antenna Multi-Path
LOS
Problem:Single Target directional methods are agnostic to user locations other than
IU. Multi-path effects and knowledge of IU location can be used to
compromise the transmission.
**Beampatterns for Illustration purposes only.
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Solution
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Solution• Problem: How can we reliably keep
eavesdroppers from decoding the IU’s data?
![Page 20: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/20.jpg)
Solution• Problem: How can we reliably keep
eavesdroppers from decoding the IU’s data?• Solution: Simultaneously Blind (actively
interfere) Eavesdroppers while serving the IU.
![Page 21: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/21.jpg)
Solution• Problem: How can we reliably keep
eavesdroppers from decoding the IU’s data?• Solution: Simultaneously Blind (actively
interfere) Eavesdroppers while serving the IU.• How: By leveraging the multi-stream/user
abilities of recent multi-antenna technologies (802.11n/ac)
![Page 22: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/22.jpg)
Solution• Problem: How can we reliably keep
eavesdroppers from decoding the IU’s data?• Solution: Simultaneously Blind (actively
interfere) Eavesdroppers while serving the IU.• How: By leveraging the multi-stream/user
abilities of recent multi-antenna technologies (802.11n/ac)– AP creates simultaneous streams
![Page 23: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/23.jpg)
Solution• Problem: How can we reliably keep
eavesdroppers from decoding the IU’s data?• Solution: Simultaneously Blind (actively
interfere) Eavesdroppers while serving the IU.• How: By leveraging the multi-stream/user
abilities of recent multi-antenna technologies (802.11n/ac)– AP creates simultaneous streams– Use one for IU
![Page 24: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/24.jpg)
Solution• Problem: How can we reliably keep
eavesdroppers from decoding the IU’s data?• Solution: Simultaneously Blind (actively
interfere) Eavesdroppers while serving the IU.• How: By leveraging the multi-stream/user
abilities of recent multi-antenna technologies (802.11n/ac)– AP creates simultaneous streams– Use one for IU– Use remaining to Blind Eavesdroppers
![Page 25: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/25.jpg)
Solution• Problem: How can we reliably keep
eavesdroppers from decoding the IU’s data?• Solution: Simultaneously Blind (actively
interfere) Eavesdroppers while serving the IU.• How: By leveraging the multi-stream/user
abilities of recent multi-antenna technologies (802.11n/ac)– AP creates simultaneous streams– Use one for IU– Use remaining to Blind Eavesdroppers
STR O B E
![Page 26: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/26.jpg)
Solution• Problem: How can we reliably keep
eavesdroppers from decoding the IU’s data?• Solution: Simultaneously Blind (actively
interfere) Eavesdroppers while serving the IU.• How: By leveraging the multi-stream/user
abilities of recent multi-antenna technologies (802.11n/ac)– AP creates simultaneous streams– Use one for IU– Use remaining to Blind Eavesdroppers
STR O B E
imultaneous
ansmissions with
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Solution• Problem: How can we reliably keep
eavesdroppers from decoding the IU’s data?• Solution: Simultaneously Blind (actively
interfere) Eavesdroppers while serving the IU.• How: By leveraging the multi-stream/user
abilities of recent multi-antenna technologies (802.11n/ac)– AP creates simultaneous streams– Use one for IU– Use remaining to Blind Eavesdroppers
STR O B E
imultaneous
ansmissions with
rthogonally
linded
avesdroppers
![Page 28: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/28.jpg)
E
STROBE Overview
Indoors (eg. Coffee Shop)
IU
E
AP
STROBE
**Beampatterns for Illustration purposes only.
![Page 29: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/29.jpg)
E
STROBE Overview
Indoors (eg. Coffee Shop)
IU
E
AP
STROBE
**Beampatterns for Illustration purposes only.
Blinding Streams
![Page 30: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/30.jpg)
E
STROBE Overview
Indoors (eg. Coffee Shop)
IU
E
AP
STROBE
**Beampatterns for Illustration purposes only.
Blinding Streams
![Page 31: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/31.jpg)
E
STROBE Overview
Indoors (eg. Coffee Shop)
IU
E
AP
STROBE
**Beampatterns for Illustration purposes only.
Blinding Streams
STROBE:
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E
STROBE Overview
Indoors (eg. Coffee Shop)
IU
E
AP
STROBE
**Beampatterns for Illustration purposes only.
Blinding Streams
STROBE:•Leverages existing multi-stream capabilities
![Page 33: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/33.jpg)
E
STROBE Overview
Indoors (eg. Coffee Shop)
IU
E
AP
STROBE
**Beampatterns for Illustration purposes only.
Blinding Streams
STROBE:•Leverages existing multi-stream capabilities•Cross-layer approach but requires minimal hardware modification (11n/ac compatible)
![Page 34: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/34.jpg)
E
STROBE Overview
Indoors (eg. Coffee Shop)
IU
E
AP
STROBE
**Beampatterns for Illustration purposes only.
Blinding Streams
STROBE:•Leverages existing multi-stream capabilities•Cross-layer approach but requires minimal hardware modification (11n/ac compatible)•Coexists with existing security protocols
![Page 35: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/35.jpg)
T
CCCC
BBBB
AAAA
wwww
wwww
wwww
HHHHW
4321
4321
43211**†
BackgroundZero Forcing Beamforming (ZFBF)
• Assume 4 Tx Antennas and 3 single-antenna receivers
4321
4321
4321
CCCC
BBBB
AAAA
hhhh
hhhh
hhhh
H hk's – H for each recv.
• Calculate weights with pseudo-inverse
wj's
• “Zero Interference” Condition
jkwh Tjk ,0)(
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Orthogonal Blinding
![Page 37: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/37.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
![Page 38: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/38.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)
![Page 39: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/39.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt
![Page 40: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/40.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt – New H matrix is unitary (pseudo-inverse is complex conjugate
transpose)
![Page 41: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/41.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt – New H matrix is unitary (pseudo-inverse is complex conjugate
transpose)– Intended user’s steering weight is equivalent to SUBF
![Page 42: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/42.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt – New H matrix is unitary (pseudo-inverse is complex conjugate
transpose)– Intended user’s steering weight is equivalent to SUBF
• Ease of implementation/integration
![Page 43: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/43.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt – New H matrix is unitary (pseudo-inverse is complex conjugate
transpose)– Intended user’s steering weight is equivalent to SUBF
• Ease of implementation/integration– ZFBF systems can use QR-decomposition (followed by
backsubstitution) to calculate pseudo-inverse
![Page 44: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/44.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt – New H matrix is unitary (pseudo-inverse is complex conjugate
transpose)– Intended user’s steering weight is equivalent to SUBF
• Ease of implementation/integration– ZFBF systems can use QR-decomposition (followed by
backsubstitution) to calculate pseudo-inverse– QR is used to implement Gram-Schmidt (existing silicon can be re-
used for STROBE)
![Page 45: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/45.jpg)
Experimental Methodology• STROBE implemented in WARPLab using ZFBF testbed
developed in:– E. Aryafar, N. Anand, T. Salonidis, and E. Knightly. Design and experimental
evaluation of multi-user beamforming in Wireless LANs. In Proc. ACM MobiCom, Chicago, Illinois, September 2010
• Performance Metric: Received signal strength (dB)
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Experimental Methodology
Scheme ComparisonsNon-
Directional
OMNI(Omni-
directional)
Single-Target Directional
SUBF(Single-User
Beamforming)
DA(Directional
Antenna)
Multi-Target Directional
CE(Cooperating
Eavesdropper)
STROBE
![Page 47: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/47.jpg)
Experimental Methodology
Unrealistic scenario in which Eavesdroppers
provide AP with their CSI to be precisely blinded.
Scheme ComparisonsNon-
Directional
OMNI(Omni-
directional)
Single-Target Directional
SUBF(Single-User
Beamforming)
DA(Directional
Antenna)
Multi-Target Directional
CE(Cooperating
Eavesdropper)
STROBE
![Page 48: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/48.jpg)
Experimental Methodology
Scheme ComparisonsNon-
Directional
OMNI(Omni-
directional)
Single-Target Directional
SUBF(Single-User
Beamforming)
DA(Directional
Antenna)
Multi-Target Directional
CE(Cooperating
Eavesdropper)
STROBE
•Fairness• Net transmit power equivalent for all schemes
![Page 49: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/49.jpg)
ExperimentsBaseline How does STROBE perform in a typical, indoor,
wireless scenario?
Relative Eavesdropper location
How does STROBE cope with varying eavesdropper proximity to IU?
How does STROBE handle eavesdroppers in-line with IU?
Verifying necessity of multi-path (outdoor)
How dependent is STROBE on multi-path scattering characteristic of indoor WLAN
environments?
Nomadic EavesdropperIs it possible for an eavesdropper to exhaustively traverse an environment to find a location where
STROBE’s performance diminishes?
![Page 50: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/50.jpg)
ExperimentsBaseline How does STROBE perform in a typical, indoor,
wireless scenario?
Relative Eavesdropper location
How does STROBE cope with varying eavesdropper proximity to IU?
How does STROBE handle eavesdroppers in-line with IU?
Verifying necessity of multi-path (outdoor)
How dependent is STROBE on multi-path scattering characteristic of indoor WLAN
environments?
Nomadic EavesdropperIs it possible for an eavesdropper to exhaustively traverse an environment to find a location where
STROBE’s performance diminishes?
![Page 51: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/51.jpg)
ExperimentsBaselineHow does STROBE perform in a typical, indoor,
wireless scenario?
Relative Eavesdropper locationHow does STROBE cope with varying eavesdropper proximity to IU?
How does STROBE handle eavesdroppers in-line with IU?
Verifying necessity of multi-path (outdoor) How dependent is STROBE on multi-path scattering characteristic of indoor WLAN environments?
Nomadic EavesdropperIs it possible for an eavesdropper to exhaustively traverse an environment to find a location where
STROBE’s performance diminishes?
![Page 52: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/52.jpg)
Baseline
![Page 53: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/53.jpg)
Baseline
![Page 54: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/54.jpg)
Baseline
0
5
10
15
20
SIN
R (
dB
)
Received SINR of transmission to IU
IU E1 E
2 E
3
Omni SUBF STROBE CE
![Page 55: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/55.jpg)
Baseline
0
5
10
15
20
SIN
R (
dB
)
Received SINR of transmission to IU
IU E1 E
2 E
3
Omni SUBF STROBE CE
• Omni - In range clients receive transmission with high SINR, distance from transmitter is not always a good predictor
![Page 56: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/56.jpg)
Baseline
0
5
10
15
20
25
SIN
R (
dB
)
Received SINR of transmission to IU
IU E1 E
2 E
3
Omni SUBF STROBE CE
• Omni - In range clients receive transmission with high SINR, distance from transmitter is not always a good predictor
![Page 57: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/57.jpg)
Baseline
0
5
10
15
20
25
SIN
R (
dB
)
Received SINR of transmission to IU
IU E1 E
2 E
3
Omni SUBF STROBE CE
• Omni - In range clients receive transmission with high SINR, distance from transmitter is not always a good predictor
• SUBF – Maximizes SINR at IU but agnostic to signal energy afterwards
![Page 58: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/58.jpg)
Baseline
0
5
10
15
20
25
SIN
R (
dB
)
Received SINR of transmission to IU
IU E1 E
2 E
3
Omni SUBF STROBE CE
• Omni - In range clients receive transmission with high SINR, distance from transmitter is not always a good predictor
• SUBF – Maximizes SINR at IU but agnostic to signal energy afterwards
![Page 59: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/59.jpg)
Baseline
0
5
10
15
20
25
SIN
R (
dB
)
Received SINR of transmission to IU
IU E1 E
2 E
3
Omni SUBF STROBE CE
• Omni - In range clients receive transmission with high SINR, distance from transmitter is not always a good predictor
• SUBF – Maximizes SINR at IU but agnostic to signal energy afterwards
• STROBE – Serves IU with high SINR, restricts E SINR to < 4dB
![Page 60: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/60.jpg)
Baseline
0
5
10
15
20
25
SIN
R (
dB
)
Received SINR of transmission to IU
IU E1 E
2 E
3
Omni SUBF STROBE CE
• Omni - In range clients receive transmission with high SINR, distance from transmitter is not always a good predictor
• SUBF – Maximizes SINR at IU but agnostic to signal energy afterwards
• STROBE – Serves IU with high SINR, restricts E SINR to < 4dB
![Page 61: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/61.jpg)
Baseline
0
5
10
15
20
25
SIN
R (
dB
)
Received SINR of transmission to IU
IU E1 E
2 E
3
Omni SUBF STROBE CE
• Omni - In range clients receive transmission with high SINR, distance from transmitter is not always a good predictor
• SUBF – Maximizes SINR at IU but agnostic to signal energy afterwards
• STROBE – Serves IU with high SINR, restricts E SINR to < 4dB
• CE – Precise blinding of E comes at the cost of SINR served to IU
![Page 62: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/62.jpg)
ExperimentsBaseline How does STROBE perform in a typical, indoor,
wireless scenario?
Relative Eavesdropper location
How does STROBE cope with varying eavesdropper proximity to IU?
How does STROBE handle eavesdroppers in-line with IU?
Verifying necessity of multi-path (outdoor)
How dependent is STROBE on multi-path scattering characteristic of indoor WLAN
environments?
Nomadic EavesdropperIs it possible for an eavesdropper to exhaustively traverse an environment to find a location where
STROBE’s performance diminishes?
![Page 63: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/63.jpg)
Nomadic Eavesdropper
![Page 64: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/64.jpg)
Nomadic EavesdropperOmni
(dB)
![Page 65: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/65.jpg)
Nomadic EavesdropperSUBF
Omni
(dB)
![Page 66: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/66.jpg)
Nomadic EavesdropperDA
Omni
SUBF
(dB)
![Page 67: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/67.jpg)
Nomadic EavesdropperSTROBE
Omni
SUBF
DA
(dB)
![Page 68: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/68.jpg)
Conclusions• Verified STROBE’s performance in indoor
environments– Functionality does not degrade with relative
eavesdropper position• STROBE’s performance depends on indoor
multi-path effects– Verified by outdoor testing
• STROBE successfully withstands attacks from a nomadic eavesdropper
• On average, STROBE provides the IU with a 15 dB stronger signal than the eavesdropper
![Page 69: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/69.jpg)
ALL EXPERIMENTS
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Orthogonal Blinding
![Page 71: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/71.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
![Page 72: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/72.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)
![Page 73: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/73.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt Orthonormalization
process
![Page 74: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/74.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt Orthonormalization
process– New H matrix is unitary (pseudo-inverse is complex conjugate transpose)
![Page 75: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/75.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt Orthonormalization
process– New H matrix is unitary (pseudo-inverse is complex conjugate transpose)– Intended user’s steering weight is equivalent to SUBF
![Page 76: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/76.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt Orthonormalization
process– New H matrix is unitary (pseudo-inverse is complex conjugate transpose)– Intended user’s steering weight is equivalent to SUBF
• Ease of implementation/integration
![Page 77: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/77.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt Orthonormalization
process– New H matrix is unitary (pseudo-inverse is complex conjugate transpose)– Intended user’s steering weight is equivalent to SUBF
• Ease of implementation/integration– ZFBF systems can use QR-decomposition (followed by backsubstitution)
to calculate pseudo-inverse
![Page 78: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/78.jpg)
Orthogonal Blinding• Limited Channel State Information (CSI)
– Only know IU’s channel (h vector)– Generate orthogonal h vectors using Gram-Schmidt Orthonormalization
process– New H matrix is unitary (pseudo-inverse is complex conjugate transpose)– Intended user’s steering weight is equivalent to SUBF
• Ease of implementation/integration– ZFBF systems can use QR-decomposition (followed by backsubstitution)
to calculate pseudo-inverse– QR is used to implement Gram-Schmidt (existing silicon can be re-used
for STROBE)
![Page 79: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/79.jpg)
ExperimentsBaseline How does STROBE perform in a typical, indoor,
wireless scenario?
Relative Eavesdropper location
How does STROBE cope with varying eavesdropper proximity to IU?
How does STROBE handle eavesdroppers in-line with IU?
Verifying necessity of multi-path (outdoor)
How dependent is STROBE on multi-path scattering characteristic of indoor WLAN
environments?
Nomadic EavesdropperIs it possible for an eavesdropper to exhaustively traverse an environment to find a location where
STROBE’s performance diminishes?
![Page 80: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/80.jpg)
Relative E Location: Proximity
![Page 81: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/81.jpg)
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
Relative E Location: Proximity
![Page 82: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/82.jpg)
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
Relative E Location: Proximity
• Omni - High SINR variability indicator of multipath effects
![Page 83: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/83.jpg)
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
Relative E Location: Proximity
• Omni/SUBF - High SINR variability indicator of multipath effects
![Page 84: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/84.jpg)
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
Relative E Location: Proximity
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
• Omni/SUBF - High SINR variability indicator of multipath effects
![Page 85: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/85.jpg)
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
Relative E Location: Proximity
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
• Omni/SUBF - High SINR variability indicator of multipath effects
• CE – Precise blinding regardless of distance, consistent results regardless of multi-path
![Page 86: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/86.jpg)
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
Relative E Location: Proximity
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
• Omni/SUBF - High SINR variability indicator of multipath effects
• CE – Precise blinding regardless of distance, consistent results regardless of multi-path
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0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
Relative E Location: Proximity
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30a. Omni
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30b. SUBF
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30c. STROBE
SIN
R (
dB)
Distance ()
IU E1
E2
E3
0 1 2 3 4 5 6 7 8 9 10
0
10
20
30d. CE
Distance ()
SIN
R (
dB)
IU E1
E2
E3
• Omni/SUBF - High SINR variability indicator of multipath effects
• CE – Precise blinding regardless of distance, consistent results regardless of multi-path
• STROBE – Mildly affected at close distances, consistent results regardless of multi-path, provides far greater SINR to IU than CE
![Page 88: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/88.jpg)
ExperimentsBaseline How does STROBE perform in a typical, indoor,
wireless scenario?
Relative Eavesdropper location
How does STROBE cope with varying eavesdropper proximity to IU?
How does STROBE handle eavesdroppers in-line with IU?
Verifying necessity of multi-path (outdoor)
How dependent is STROBE on multi-path scattering characteristic of indoor WLAN
environments?
Nomadic EavesdropperIs it possible for an eavesdropper to exhaustively traverse an environment to find a location where
STROBE’s performance diminishes?
![Page 89: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/89.jpg)
Relative E Location: In-Line
![Page 90: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/90.jpg)
Relative E Location: In-Line
![Page 91: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/91.jpg)
Relative E Location: In-Line Omni – SINR not predicted by location in line
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Relative E Location: In-Line Omni – SINR not predicted by location in line
• SUBF – Single-target directional scheme; to defeat, get in LOS
![Page 93: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/93.jpg)
Relative E Location: In-Line Omni – SINR not predicted by location in line
• SUBF – Single-target directional scheme; to defeat, get in LOS
• STROBE – Multiple eavesdroppers in direct LOS between IU and Tx are successfully blinded
![Page 94: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/94.jpg)
Relative E Location: In-Line Omni – SINR not predicted by location in line
• SUBF – Single-target directional scheme; to defeat, get in LOS
• STROBE – Multiple eavesdroppers in direct LOS between IU and Tx are successfully blinded
• CE – Precise blinding comes at a price.
![Page 95: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/95.jpg)
ExperimentsBaseline How does STROBE perform in a typical, indoor,
wireless scenario?
Relative Eavesdropper location
How does STROBE cope with varying eavesdropper proximity to IU?
How does STROBE handle eavesdroppers in-line with IU?
Verifying necessity of multi-path (outdoor)
How dependent is STROBE on multi-path scattering characteristic of indoor WLAN
environments?
Nomadic EavesdropperIs it possible for an eavesdropper to exhaustively traverse an environment to find a location where
STROBE’s performance diminishes?
![Page 96: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/96.jpg)
Verifying necessity of Multi-PathOutdoors
![Page 97: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/97.jpg)
Verifying necessity of Multi-PathOutdoors
![Page 98: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/98.jpg)
Verifying necessity of Multi-PathOutdoors
![Page 99: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/99.jpg)
Verifying necessity of Multi-PathOutdoors
Multi-Stream methods fail outdoors
![Page 100: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/100.jpg)
Verifying necessity of Multi-PathOutdoors
Multi-Stream methods fail outdoors
• STROBE becomes directional
![Page 101: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/101.jpg)
Verifying necessity of Multi-PathOutdoors
Multi-Stream methods fail outdoors
• STROBE becomes directional
• CE completely fails
![Page 102: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/102.jpg)
BACKUP SLIDES
![Page 103: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/103.jpg)
Prior Work
![Page 104: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/104.jpg)
Prior Work• Beamforming-based multiple AP cooperation
![Page 105: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/105.jpg)
Prior Work• Beamforming-based multiple AP cooperation
• Information theoretic multi-antenna security
![Page 106: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/106.jpg)
Prior Work• Beamforming-based multiple AP cooperation
1. J. Carey and D. Grunwald. Enhancing WLAN security with smart antennas: a physical layer response for information assurance. In Proc. IEEE Vehicular Technology Conference, September 2004.
• Information theoretic multi-antenna security
![Page 107: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/107.jpg)
Prior Work• Beamforming-based multiple AP cooperation
1. J. Carey and D. Grunwald. Enhancing WLAN security with smart antennas: a physical layer response for information assurance. In Proc. IEEE Vehicular Technology Conference, September 2004.
2. S. Lakshmanan, C. Tsao, R. Sivakumar, and K. Sundaresan. Securing Wireless Data Networks against Eavesdropping using Smart Antennas. In The 28th International Conference on Distributed Computing Systems, Beijing, China, June 2008.
• Information theoretic multi-antenna security
![Page 108: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/108.jpg)
Prior Work• Beamforming-based multiple AP cooperation
1. J. Carey and D. Grunwald. Enhancing WLAN security with smart antennas: a physical layer response for information assurance. In Proc. IEEE Vehicular Technology Conference, September 2004.
2. S. Lakshmanan, C. Tsao, R. Sivakumar, and K. Sundaresan. Securing Wireless Data Networks against Eavesdropping using Smart Antennas. In The 28th International Conference on Distributed Computing Systems, Beijing, China, June 2008.
• Information theoretic multi-antenna security1. S. Goel and R. Negi. Guaranteeing secrecy using artificial noise.
IEEE Transactions on Communications, 7(6):2180–2189, June 2008.
![Page 109: STROBE Actively Securing Wireless Communications using Zero-Forcing Beamforming Narendra Anand Rice University Sung-Ju Lee HP Labs Edward Knightly Rice](https://reader038.vdocuments.site/reader038/viewer/2022103122/56649cdf5503460f949a93b1/html5/thumbnails/109.jpg)
Prior Work• Beamforming-based multiple AP cooperation
1. J. Carey and D. Grunwald. Enhancing WLAN security with smart antennas: a physical layer response for information assurance. In Proc. IEEE Vehicular Technology Conference, September 2004.
2. S. Lakshmanan, C. Tsao, R. Sivakumar, and K. Sundaresan. Securing Wireless Data Networks against Eavesdropping using Smart Antennas. In The 28th International Conference on Distributed Computing Systems, Beijing, China, June 2008.
• Information theoretic multi-antenna security1. S. Goel and R. Negi. Guaranteeing secrecy using artificial noise.
IEEE Transactions on Communications, 7(6):2180–2189, June 2008.
2. L. Dong, Z. Han, A. Petropulu, and V. Poor. Improving wireless physical layer security via cooperating relays. IEEE Transactions on Signal Processing, 58(3):1875–1888, March 2010.