Friday, September 18, 2009

SDR helps to crack GSM

Episode 213 of the Security Now netcast discussed the topic of cracking GSM cell phone security. The episode reported on work that has been underway for several years to demonstrate the vulnerability of GSM to cracking, and how present-day hardware and software make this very feasible compared with the outlook of the GSM Association. The latest developments have been reported by cnet news and many other sources.

Starting at page 10 of the Security Now PDF transcript, Steve Gibson describes the weakness of GSM's encryption technology. At page 12 he discusses the current approach for cracking GSM that makes use of:
  • A Universal Software Radio Peripheral available from Ettus. This provides the necessary radio hardware. A 7-inch receiver board with appropriate daughterboards can tune the radio frequencies of interest and capture a wide swath of RF spectrum via USB or Gigabit Ethernet interface.
  • The GNU Software Radio, which provides free, open source software to accomplish the needed signal processing.
  • A distributed computing project to crack the encryption and compile it into a code book
Security Now episode 214 contains some feedback about the different versions of encryption used by GSM.

This project to explore and demonstrate the vulnerability of GSM encryption provides an example of the emerging power of SDR technology.

Tuesday, April 7, 2009

The Universal Handset

The April 2009 issue of IEEE Spectrum includes a short article The Universal Handset which describes how SDR will enable handsets to speak WiFi, 3G, WiMAX and more. It recounts the origins of SDR in 1992 and focuses on how this technology will be applied to future handset designs. The hardware and software challenges are also described.