I will be previewing one S4 2009 paper each week. Digital Bond’s SCADA Security Scientific Symposium is Jan 21-22 in Miami Beach with an advanced control system security course on Jan 20th. See the full agenda with detailed paper descriptions and register to be a physical or virtual S4 attendee.

This first preview deals with a subject rarely discussed because it is outside the area of expertise of most IT and control system security professionals.

Jamming and Interference Induced Denial of Service Attacks on IEEE 802.15.4 Based Wireless Networks

Most of the discussion on wireless control system security, whether it be ISA 100, WirelessHART, Zigbee or other 802.15.4 based protocols, has focused on authentication, encryption and other security technologies at layer 3 and above. Jake Brodsky and Anthony McConnell of the Washington Surburban Sanitary Commission will present a paper discussing if all that protection is moot. Can an adversary or unintended broadcast attack the physical layer and jam or interfer with the wireless signal to create a denial of service condition?

It’s hard to believe that there has been very little theoretical work and even less practical testing on this important topic. The intent of the paper is to review the validity of IEEE 802.15.4 Annex E, to verify the performance of an adjacent band carrier interference source, and even an ISM band carrier. Pulsed signal attacks, with the pulse width and repetition rates designed to hit each OFDM carrier on every channel, or to match the spread spectrum chip rate, will also be evaluated. Jamming/interference ranges will be discussed mostly in terms of decibel differences.

Improvements in security and availability when using antennas to focus radio energy toward particular areas of interest and to exclude other areas of interest are discussed. There is at least one particular insight that ought to raise many eyebrows (and no, it’s not about polarization).

This is actually the first of two papers on 802.15.4. The second paper deals with Layer 2 hardware attacks and will be previewed next week.