Energy Management in Secure Mobile Environment

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Energy ManagementinSecure Mobile Environment

• Ramesh Karri, Piyush Mishra
• CAD LAB
• Department of Electrical and Computer Engineering
• Polytechnic University
• Brooklyn, NY

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Outline

• Design policies for energy-efficient secure
  wireless sessions
• Develop a mobile test bed for accurate and
  efficient energymeasurements
• Benchmark power consumption and performance
  characteristics of the mobile test bed
• Software implementations of DES, 3DES, AES
  encryption algorithms
• WLAN card (modes of operation RF signal power
  level)
• Software implementation of DEFLATE data
  compression algorithms
• Develop technique to minimize the energy
  consumed by a securewireless session and study
  the security vs. energy trade-offs

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Mobile Test Bed
Spectrum24 11 Mbps network adapter card
Tektronix TDS 3054 Oscilloscope
Sycard PCI 100 extender card
?
To the Li-ion 4 V battery
Symbol PPT 2800
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Tektronix TCP 202 current probe

• Symbol PPT 2800 SA-1110 206 MHz processor, 16
  MB RAM, 16 MBFLASH ROM, 16 KB Instruction cache,
  8 KB data cache
• Tektronix TDS 3054 oscilloscope 4 channel, 500
  MHz, 5 GS/s
• Tektronix TCP 202 current probe DC to 50 MHz,
  15A DC Peak AC,Minimum sensitivity 10 mA/div,
  DC accuracy ?1 with probe calibrator

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Session Negotiation
Protocol Optimization

• Session negotiation Server looks up client
  certificate from its own source
• Session refresh Combine previous session
  association with newly exchanged random values to
  generate new session parameters
• Protocol message compression

Choice of Key Exchange
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Data Encryption
Choice of Data Encryption algorithm

• Optimized for throughput, entire code
  (instructiondata) running from cache
• 16 KB instruction cache, 8 KB write back data
  cache (32-way set associative)

Hardware implementation
Pros Faster, Less power, More secure Cons
Cost, More area
Encrypting and transmitting (P1 mode) 1000 UDP
packets (600 bytes/packet)
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Data Transaction

• Compression reduces the energy consumed by data
  transaction (both transmission reception),
  cryptographic computations, idle system and
  messages exchanged during session negotiation

• Two important observations for energy efficiency
• Optimum parameter selection to tradeoff
  compression ratio vs. energy
• Matching the compression block (CB) size to the
  data cache size

CL Compression level, ML Memory level 1 Calgary
corpus benchmark
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Choice of RF signal power

• Power consumed by WLAN card f (RF signal
  power)
• Designing policies for dynamic RF signal power
  configuration based on WLAN card power
  characteristics, distance from the access point
  and network conditions is highly desirable