Pattern Regulator for Wireless Body Sensor
Networks
Lan Yao
Northeastern University
Shenyang, China 110819
Email: yaolan@mail.neu.edu.cn
Fuxiang Gao
Northeastern University
Shenyang, China 110819
Email: gaofuxiang@mail.neu.edu.cn
Ge Yu
Northeastern University
Shenyang, China 110819
Email: yuge@mail.neu.edu.cn
Abstract—In a wireless body area sensor network (WBAN),
biosensors are implanted or worn on an individual to acquire
medical data for a clinical diagnosis or physical monitoring.
Traditionally, authentication and cryptography techniques are
used to achieve the data confidentiality and privacy of a WBAN
system. However, for WBAN systems, besides data itself, the
pattern of data transmission may leak critical information about
the user. For example, various medical sensors deliver data in
different patterns and these patterns leak many critical facts, e.g.,
what sensors are used (which implies diseases the individual may
have), and how frequent the sensor is sampling (which implies
how urgent some abnormal observation is about a patient). In
this work, to address this challenge, we design a regulator, which
packs real data session into a type-independent transmission
model at transmission layer. All valid data packets are equably
sent at the frequency defined by the regulator and at the same
length to clutter the inherent pace of valid data transmission and
other parameters. We also propose a strategy PAS to minimize the
overhead while preventing attackers from locating the patients.
Our extensive experiments validate our regulator and PAS design.
Index Terms—Wireless Body Networks; pattern detection;
regulator; ML
I. INTRODUCTION
With the evolution of biometrical sensor and mobile com-
puting, a wearable healthcare system which is called Wireless
Body Area Network (WBAN) has been used to monitor and
record medical data from an individual and transmit them
through wireless communication to a data server. This data
plays a significant role as an auxiliary for diagnosis or treat-
ment of diseases. Especially for chronic patients or the elder,
WBAN has potential of enhancing real-time data collection,
reducing cost and decreasing hospital visiting times [22]. In
past few years, some innovative methods about WBAN for
healthcare have been developed [4], [7], [11], [25]. They serve
as important parts to monitor cardiac, EEG, heart-rate, SPO2
or respiration data from a patient for further diagnosis or
healthcare. Other extra physical data such as acceleration, gyro
and elevation coulbe also be collected through WBAN for
posture and activity monitoring, which is been used for tumble
alarm and prediction. Another application is electric-training
for athletics [6].
All these systems provide us preliminary applications for
physical monitoring, which must meet increasingly stringent
security (e.g., confidentiality) and privacy requirements for
medical data and patients. Recently, many novel approaches
[1], [8], [19], [24], [27], [29] have been proposed to address
various security and privacy challenges in wireless body area
sensor networks. A wireless body area sensor network is
vulnerable to various attacks due to many limitations of
devices and some unique features of usage of medical sensors,
for example, (1) uncontrolled wireless communication envi-
ronment; (2) limited computing, storage and energy resource
of light-weight medical sensor nodes; (3) dynamic but often
fixed duty cycles of using medical sensors; and (4) dynamic
but often predictable data packet sizes, transmission frequency,
and data values for medical sensors. For example, based
on the specification [15], a specific medical sensor will
report its collected value in a predefined duty cycle pattern
and each data packet will often have a pre-defined length.
Various attacks (both active and passive attacks) may happen
in data sensing, routing, data storage and management. For
example, an illegimate wireless sink will launch a Selective
Forwarding or Worm-hole attacks; sensor nodes exhaust their
energy by receiving unauthenticated packets from attackers
[13]; unverified data or forged data will lead a chaos to medical
records ; a false relay could modify the medical data and then
forward it to the server [21]. These attacks may be prevented
by carefully designing and deploying data encryption and
authentication methods [16].
In addition to these active attacks, WBAN is susceptible
to more passive attacks than ordinary sensor networks, e.g.,
sometimes a simple eavesdropping attack will reveal the data
or the pattern of data collection by the sensor nodes, which
in turn could breach the security and privacy of WBAN
applications. In this work we focus on a not-well-studied
problem: how to prevent a passive attackers from inferring
some critical information about the patients by eavesdropping
the communication. Notice that active attacks often will either
inject false data, or modify the data, or intercept the data
communicated between the sensor nodes and the receiving sink
node. On the other hand, a passive attacker, by eavesdropping
the communication, could track the signals from medical
sensor and then locate the source even the data is encrypted;
or learn the fact that an individual is using a health monitoring
system; or find out the exact types of medical sensors used by
the patient; or analyze the duty-cycle pattern of data collection;
or acquire partial data by studying some correlation among the
2013 IEEE International Conference on High Performance Computing and Communications & 2013 IEEE International Conference
on Embedded and Ubiquitous Computing
978-0-7695-5088-6/13 $26.00 © 2013 IEEE
DOI 10.1109/HPCC.and.EUC.2013.219
1558
2013 IEEE International Conference on High Performance Computing and Communications & 2013 IEEE International Conference
on Embedded and Ubiquitous Computing
978-0-7695-5088-6/13 $31.00 © 2013 IEEE
DOI 10.1109/HPCC.and.EUC.2013.219
1558