Lancaster research
reveals that WiFi signals can be used to detect tampering with
connected devices
such as wireless security cameras
(December 18, 2015) Physical
attacks on devices connected to the Internet can be detected by analysing WiFi
signals, computer scientists have discovered.
Wireless devices are increasingly used for critical roles,
such as security systems or industrial plant automation. Although wireless
transmissions can be encrypted to protect transmitted data, it is hard to
determine if a device – such as a wirelessly connected security camera
protecting critical buildings in airports or power stations – has been tampered
with. An attacker may simply rotate a camera’s view away from the area it is
guarding without triggering an alert.
Researchers at Lancaster University, in their study ‘Using
Channel State Information for Tamper Detection in the Internet of Things’ have
created a method that analyses WiFi signals at multiple receivers to detect
physical attacks. A change in the pattern of wireless signals – known as
Channel State Information (CSI) – picked up by the receivers can indicate a
tamper situation. The algorithm detects attacks despite signal noise caused by
natural changes to the environment such as people walking through the
communication paths.
Dr Utz Roedig, Reader in Lancaster University’s School of
Computing and Communications and one of the report’s authors, said: “A large
number of Internet of Things systems are using WiFi and many of these require a
high level of security. This technique gives us a new way to introduce an
additional layer of defence into our communication systems. Given that we use
these systems around critically important infrastructure this additional
protection is vital.”