Quantum Encryption in a Wireless World

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Quantum Encryption in a Wireless World

• Presentation by
• Jack Hughes

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Topics

• Review of Papers
• Quantum Key Distribution The Science of Secret
  Communications LA-UR-04-8691
• by Richard J. Hughes Physics Division Los Alamos
  National Laboratory
• A Survey of 802.11a Wireless Security Threats and
  Security Mechanisms ITOC-TR-2003-101
• by Colonel Donald J. Welch Ph.D. U.S. Army
• Major Scott D. Lathrop U.S. Army

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Topics Continued

• Review of Papers cont.
• Security Considerations for WiMAX-based Converged
  Networks
• by Ramana Mylarvarapu for rfdesign.com August
  2005
• Area of New Research
• Quantum Encryption in a Wireless World

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Quantum Key Distribution The Science of Secret
Communications

• Abstract
• Quantum key distribution (QKD) uses single photon
  communications to securely transfer cryptographic
  keys that are required for secure communications.
  I will describe the theory of QKD and its
  implementation in both optical fiber and
  free-space.
• Relevance
• Good overview of the principles of QKD
• Lines of Research
• Limitations

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Quantum Key Distribution The Science of Secret
Communications
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Quantum Key Distribution The Science of Secret
Communications
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Quantum Key Distribution The Science of Secret
Communications
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Quantum Key Distribution The Science of Secret
Communications
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Quantum Key Distribution The Science of Secret
Communications
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Quantum Key Distribution The Science of Secret
Communications

• Alice and Bob
• Protocol is 50 efficient (with no noise!)
• Alice and Bob cannot predict which bits they will
  share

• Eve
• Cannot passively monitor the quantum channel
• Public channel conveys no info about secret data
  bits
• Public channel is authenticated

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Quantum Key Distribution The Science of Secret
Communications

• Good News
• No passive eavesdropping
• May offer one time pad level security in the
  future
• Proven secure method of sharing keys

• Bad News
• Not immune to DoS
• (But what is)
• Still requires method of authentication for
  public channel
• Biometrics?

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A Survey of 802.11a Wireless Security Threats and
Security Mechanisms

• Executive Summary (Edited)
• This white paper first describes taxonomy of
  wireless LAN attack techniques.
• We then describe the generic mechanisms
  available for authentication of users and the
  protection of the privacy and integrity of the
  data.
• We conduct a basic analysis of each security
  countermeasure by looking at the attack
  techniques addressed by the mechanism.
• We conclude by stating our recommendations for
  WLANs. These recommendations include
• Mutual Authentication
• Layer two encrypted tunnel
• Strong cryptographic integrity verification

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Quantum Key Distribution The Science of Secret
Communications
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Wireless and Eavesdropping

• Wireless systems
• Omnidirectional
• Easy to intercept packets
• Directional
• More difficult to collect packets
• Easier than wired networks
• Easier access
• Point to point
• Most difficult to collect packets
• Often used at tall heights for line of sight
  advantage

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A Survey of 802.11a Wireless Security Threats and
Security Mechanisms
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A Survey of 802.11a Wireless Security Threats and
Security Mechanisms

• Good News
• With a strong encryption algorithm and the use of
  layer 2 tunneling protocols, The channel is very
  secure against many attacks

• Bad News
• Many businesses do not completely understand
  wireless insecurity and do not take proper
  precautions
• Wireless is inherently susceptible to
  eavesdropping

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OH NO!

• Most wireless systems are NOT point to point
• QKD requires line of sight
• Where can we use QKD?

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Security Considerations for WiMAX-based Converged
Networks

• WiMax
• Worldwide Interoperability for Microwave Access
• AKA IEEE 802.16.
• WiMAX standard was drafted with security in mind,
  offering more robust protection in the form of
  certificate-based encryption.
• Still have problems
• Client impersonation
• Server impersonation
• Message tampering
• Session tampering/hijacking
• Signaling requests resulting in DoS attacks

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WiMAX flavors

• non-line-of-sight
• Where a small antenna on your computer connects
  to the tower. Uses 2 GHz to 11 GHz (similar to
  WiFi).
• Lower-wavelength transmissions are not as easily
  disrupted by physical obstructions -- they are
  better able to diffract, or bend, around
  obstacles.
• line-of-sight
• Fixed dish antenna points straight at the WiMAX
  tower from a rooftop or pole.
• Stronger and more stable, so it's able to send a
  lot of data with fewer errors.
• Line-of-sight transmissions use higher
  frequencies, with ranges reaching a possible 66
  GHz. At higher frequencies, there is less
  interference and lots more bandwidth.

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Integrating Quantum with Wireless

• Use a line of sight optical connection in
  parallel with point to point WiMAX
• Use BB84 or more advanced protocols for passing
  keys

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Summary

• QKD offers resistance to attacks that rely on
  eavesdropping
• Non-optical wireless is inherently susceptible to
  eavesdropping

• It seems like a match made in

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Summary

• However, most non-optical wireless is not point
  to point.
• Use of point to point quantum communications in
  air has already been shown
• But only a few non-optical wireless applications
  exist
• Satellite
• WiMax

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Summary

• Even if a QKD link is used with a non-optical
  wireless point to point link, We still need
  strong mutual authentication.
• Possible use of QKD link with WiMax should be
  explored

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Thank You

• Please visit
• http//www.cse.sc.edu/hughesjm/