Skip to main content
  • Submit
  • About
    • Editorial Board
    • PNAS Staff
    • FAQ
    • Accessibility Statement
    • Rights and Permissions
    • Site Map
  • Contact
  • Journal Club
  • Subscribe
    • Subscription Rates
    • Subscriptions FAQ
    • Open Access
    • Recommend PNAS to Your Librarian
  • Log in
  • My Cart

Main menu

  • Home
  • Articles
    • Current
    • Special Feature Articles - Most Recent
    • Special Features
    • Colloquia
    • Collected Articles
    • PNAS Classics
    • List of Issues
  • Front Matter
  • News
    • For the Press
    • This Week In PNAS
    • PNAS in the News
  • Podcasts
  • Authors
    • Information for Authors
    • Editorial and Journal Policies
    • Submission Procedures
    • Fees and Licenses
  • Submit
  • About
    • Editorial Board
    • PNAS Staff
    • FAQ
    • Accessibility Statement
    • Rights and Permissions
    • Site Map
  • Contact
  • Journal Club
  • Subscribe
    • Subscription Rates
    • Subscriptions FAQ
    • Open Access
    • Recommend PNAS to Your Librarian

User menu

  • Log in
  • My Cart

Search

  • Advanced search
Home
Home

Advanced Search

  • Home
  • Articles
    • Current
    • Special Feature Articles - Most Recent
    • Special Features
    • Colloquia
    • Collected Articles
    • PNAS Classics
    • List of Issues
  • Front Matter
  • News
    • For the Press
    • This Week In PNAS
    • PNAS in the News
  • Podcasts
  • Authors
    • Information for Authors
    • Editorial and Journal Policies
    • Submission Procedures
    • Fees and Licenses

New Research In

Physical Sciences

Featured Portals

  • Physics
  • Chemistry
  • Sustainability Science

Articles by Topic

  • Applied Mathematics
  • Applied Physical Sciences
  • Astronomy
  • Computer Sciences
  • Earth, Atmospheric, and Planetary Sciences
  • Engineering
  • Environmental Sciences
  • Mathematics
  • Statistics

Social Sciences

Featured Portals

  • Anthropology
  • Sustainability Science

Articles by Topic

  • Economic Sciences
  • Environmental Sciences
  • Political Sciences
  • Psychological and Cognitive Sciences
  • Social Sciences

Biological Sciences

Featured Portals

  • Sustainability Science

Articles by Topic

  • Agricultural Sciences
  • Anthropology
  • Applied Biological Sciences
  • Biochemistry
  • Biophysics and Computational Biology
  • Cell Biology
  • Developmental Biology
  • Ecology
  • Environmental Sciences
  • Evolution
  • Genetics
  • Immunology and Inflammation
  • Medical Sciences
  • Microbiology
  • Neuroscience
  • Pharmacology
  • Physiology
  • Plant Biology
  • Population Biology
  • Psychological and Cognitive Sciences
  • Sustainability Science
  • Systems Biology
QnAs

QnAs with H. Vincent Poor

Farooq Ahmed
PNAS February 14, 2017 114 (7) 1437-1438; first published January 26, 2017; https://doi.org/10.1073/pnas.1621407114
Farooq Ahmed
  • Find this author on Google Scholar
  • Find this author on PubMed
  • Search for this author on this site

See related content:

  • Wireless physical layer security
    - Dec 27, 2016
  • Article
  • Figures & SI
  • Info & Metrics
  • PDF
Loading

The proliferation of wireless devices in the last three decades has been heralded as a technological revolution. H. Vincent Poor, the Michael Henry Strater University Professor at Princeton University, has been studying these devices and the networks on which they run since their infancy, and has helped usher in the revolution. With a background in information theory, electrical engineering, and computer science, Poor has led formative research on signal processing, social networks, multiuser communications, and smart grids. PNAS recently spoke to Poor, who was elected to the National Academy of Sciences in 2011, about his current research.

Figure1
  • Download figure
  • Open in new tab
  • Download powerpoint

H. Vincent Poor. Image courtesy of David Kelly Crow (photographer).

PNAS:Your recent work examines security in the physical layer of wireless transmission. What is the physical layer, and why is security in this layer crucial?

Poor:Networks operate through multiple layers of infrastructure that encode, transmit, route, regulate, and decode information. Layering is a very important part of network design, and it is one of the reasons why networks are ubiquitous. The advantage of having layers is that you can innovate in one layer without having to redesign the whole network every time. The physical layer refers to the actual medium through which signals travel and carry information. In the case of wireless, this is basically the ether through which radio signals are transmitted.

Layered infrastructures help secure data transmission, but not all networks are created equally. Higher-layer security, which is used on networks such as the cellular network, simply isn’t practical in networks like mobile ad hoc networks, in which messages are passed from mobile terminal to mobile terminal until they reach their destination. In this situation, it is difficult and inefficient to manage conventional methods of network security. Similarly, the kind of devices that are envisioned for the so-called Internet of Things won't have a lot of computing power to implement encryption algorithms. Security in the physical layer ensures that information transmitted in these kinds of networks can be protected.

PNAS:What are some of the issues associated with incorporating physical security into the wireless layer?

Poor:First, we must understand that security is a whole portfolio of different issues. It’s not just the confidentiality of messages, but also user authentication, message integrity, and so forth. My Inaugural Article (1), coauthored with Rafael Schaefer of the Technical University of Berlin, summarizes the history and recent advances in wireless physical layer security, and also discusses some of the challenges, including practical security-code design, which is far from mature. Authentication is also a major practical issue. A set of questions also arises in how physical layer secrecy interacts with higher network layers. We’ve done some work along those lines, but there is a lot remaining. This is partly why I wanted to write this article for PNAS: so that others may be motivated to join this research effort.

PNAS:How can you use properties inherent in radio transmission, diffusion and superposition for example, to enable security in the physical layer?

Poor:The concept relates back to research conducted by Aaron Wyner at Bell Labs in the 1970s on the “wiretap channel.” Wyner was thinking about security in telephone lines, but the principles apply to wireless architectures as well. The combination of diffusion, which is essentially broadcast, and superposition, which is the addition of multiple signals in a medium, means that when you transmit a radio signal terrestrially it’s going to reflect off of intervening objects, and then when the reflections get to a receiver, they add constructively and destructively; this results in self-interference or fading. Fading depends on the geometry of the radio channel and so will differ from receiver to receiver. Fading fluctuations allow an eavesdropper’s receiver to be degraded over time, which provides opportunities for secure transmissions.

Another way that you can take advantage of the superposition property is a classical technique for degrading receivers, namely jamming, although we tend to use more sophisticated and surgical techniques these days. The use of multiple antennas also allows you to transmit in ways so that you simultaneously favor the intended receiver and degrade an eavesdropper.

PNAS:Are there systems that currently take advantage of the physical layer for security?

Poor:This is primarily a research field now, although it is beginning to move into practice. There are prototypes, and the concept has received attention from industry and start-ups.

PNAS:You began working on wireless networks in the early 1980s. Did you envision how ubiquitous they would become?

Poor:When I started in this field, the modern era of wireless was just beginning, but the cellular concept goes back to the 1940s. It wasn’t until the advent of smaller, more powerful and energy-efficient semiconductor devices that it was possible to think about developing the personal wireless communication devices we have today. For a 30-year-old technology, wireless technology has grown incredibly. It’s one of the most rapidly adopted technologies of our time or maybe of any time. It has become so much more than what people envisioned when it first emerged, and it continues to evolve at a very rapid pace.

Footnotes

    • This is a QnAs with a recently elected member of the National Academy of Sciences to accompany the member’s Inaugural Article on page 19 in issue 1 of volume 114.

    View Abstract

    References

    1. ↵
      1. Poor HV,
      2. Schaefer RF
      (2016) Wireless physical layer security. Proc Natl Acad Sci USA 114(1):19–26.
      .
      OpenUrl
    PreviousNext
    Back to top
    Article Alerts
    Email Article

    Thank you for your interest in spreading the word on PNAS.

    NOTE: We only request your email address so that the person you are recommending the page to knows that you wanted them to see it, and that it is not junk mail. We do not capture any email address.

    Enter multiple addresses on separate lines or separate them with commas.
    QnAs with H. Vincent Poor
    (Your Name) has sent you a message from PNAS
    (Your Name) thought you would like to see the PNAS web site.
    CAPTCHA
    This question is for testing whether or not you are a human visitor and to prevent automated spam submissions.
    Citation Tools
    QnAs with H. Vincent Poor
    Farooq Ahmed
    Proceedings of the National Academy of Sciences Feb 2017, 114 (7) 1437-1438; DOI: 10.1073/pnas.1621407114

    Citation Manager Formats

    • BibTeX
    • Bookends
    • EasyBib
    • EndNote (tagged)
    • EndNote 8 (xml)
    • Medlars
    • Mendeley
    • Papers
    • RefWorks Tagged
    • Ref Manager
    • RIS
    • Zotero
    Request Permissions
    Share
    QnAs with H. Vincent Poor
    Farooq Ahmed
    Proceedings of the National Academy of Sciences Feb 2017, 114 (7) 1437-1438; DOI: 10.1073/pnas.1621407114
    Digg logo Reddit logo Twitter logo Facebook logo Google logo Mendeley logo
    • Tweet Widget
    • Facebook Like
    • Mendeley logo Mendeley
    Proceedings of the National Academy of Sciences: 114 (7)
    Table of Contents

    Submit

    Sign up for Article Alerts

    Jump to section

    • Article
      • Footnotes
      • References
    • Figures & SI
    • Info & Metrics
    • PDF

    You May Also be Interested in

    Abstract depiction of a guitar and musical note
    Science & Culture: At the nexus of music and medicine, some see disease treatments
    Although the evidence is still limited, a growing body of research suggests music may have beneficial effects for diseases such as Parkinson’s.
    Image credit: Shutterstock/agsandrew.
    Scientist looking at an electronic tablet
    Opinion: Standardizing gene product nomenclature—a call to action
    Biomedical communities and journals need to standardize nomenclature of gene products to enhance accuracy in scientific and public communication.
    Image credit: Shutterstock/greenbutterfly.
    One red and one yellow modeled protein structures
    Journal Club: Study reveals evolutionary origins of fold-switching protein
    Shapeshifting designs could have wide-ranging pharmaceutical and biomedical applications in coming years.
    Image credit: Acacia Dishman/Medical College of Wisconsin.
    White and blue bird
    Hazards of ozone pollution to birds
    Amanda Rodewald, Ivan Rudik, and Catherine Kling talk about the hazards of ozone pollution to birds.
    Listen
    Past PodcastsSubscribe
    Goats standing in a pin
    Transplantation of sperm-producing stem cells
    CRISPR-Cas9 gene editing can improve the effectiveness of spermatogonial stem cell transplantation in mice and livestock, a study finds.
    Image credit: Jon M. Oatley.

    Similar Articles

    Site Logo
    Powered by HighWire
    • Submit Manuscript
    • Twitter
    • Facebook
    • RSS Feeds
    • Email Alerts

    Articles

    • Current Issue
    • Latest Articles
    • Archive

    PNAS Portals

    • Anthropology
    • Chemistry
    • Classics
    • Front Matter
    • Physics
    • Sustainability Science
    • Teaching Resources

    Information

    • Authors
    • Editorial Board
    • Reviewers
    • Librarians
    • Press
    • Site Map
    • PNAS Updates

    Feedback    Privacy/Legal

    Copyright © 2021 National Academy of Sciences. Online ISSN 1091-6490