Sensors and Wireless Communication for Medical Care

1
Sensors and Wireless Communication for Medical
Care

• Anu Bhargava and Michael Zoltowski
• CERIAS and ECE Department
• Purdue University
• West Lafayette, IN 47907
• abhargav_at_purdue.edu
• mikedz_at_ecn.purdue.edu
• Presented by Anu Bhargava

This research is supported by CERIAS security
center and NSF REU grant of Prof. Arif Ghafoor
and Mike Zoltowski.
2
Security and Safety

• Medical care environments are vulnerable to
  malicious behavior, hostile setting, terrorism
  attacks, natural disaster, tampering.
• Computing nodes and sensors can be malicious,
  selfish, malfunctioning, or compromised.
• Challenge is to develop sensors that detect and
  monitor violations in medical care environments
  before threat to life occurs.
• Reliability, Security, Accuracy can affect
  timeliness and precise information for patient
  monitoring.
• Collaboration among physicians/nurses,
  pharmacies, emergency personnel, law enforcement
  agencies, government/community leaders over
  wireless network should be secure, private,
  reliable, consistent/correct and anonymous.

3
Technology and Type of Sensors

• Sensors and wireless devices have limited
  computation, communication, and energy.
• High rate of temporary or lasting failure.
• Tiny, inexpensive, mobile sensors are becoming
  available.
• Microsensors consist of 8-bit 4-MHz processors.
• Bio-sensors to detect Anthrax, viruses, toxins,
  bacteria uses chips coated with antibodies that
  attract a specific biological agent. Pattern
  changes result in alerts.
• Ion trap mass spectrometer aids in locating
  fingerprints of proteins to detect toxin or
  bacteria.
• Neutron-based detectors detect chemical and
  nuclear materials.
• Research is underway on sensor fusion, topology
  management, smart dust, scalability, and wireless
  communication issues.
• Characteristics of sensors include size, battery
  consumption, energy level, movement, position,
  redundancy, failure mode (failed, degrading,
  Byzantine).

4
Research Issues

• Smart Antennae
• Omni-directional antenna has a problem with
  congestion and eavesdropping. One solution is
  smart antennae with multiple sub-antennae and
  switches (sectorized, phase array, and adaptive
  array).
• Sectorized has elements that aim in different
  directions and only one sector is energized with
  Radio Frequency.
• Phase-array can steer a main lobe in any
  direction, but not capable of forming nulls.
• Adaptive-arrays can form multiple main lobes and
  steerable nulls in the direction of interferes.
• Jam Resistant Antennae
• Two antennae on each device and use polarization
  in a way to receive signals from one direction.
  Channel estimation possible when distinct
  antennae have different polarization or
  significant spatial separation.

5

• Fault-tolerant Authentication
• If base station fails, use backup controller in
  the immediate neighborhood.
• Hierarchy of base stations with multiple keys can
  be used.
• Denial of Service Attacks and Intruder
  Identification
• Flooding by a malicious host, impersonation, gang
  attack, Byzantine behavior.
• Suspicion lists, black list can be created to
  ignore sensors.
• Privacy and Anonymity
• Location of sensor.
• Source of data.
• False accusation.
• HIPPA regulations for medical data.
• Limited access and disclosure.
• Energy Conservation
• Aggregation of data and pattern identification.
• Routers need to be computationally efficient for
  energy.

6
Sensors in a Patients Environment

• Safety and Security in Patients Room
• Monitor the entrance and access to a patients
  room.
• Monitor pattern of activity with respect to
  devices connected to a patient.
• Protect patients from neglect, abuse, harm,
  tampering, movement of patient outside the safety
  zone.
• Monitor visitor clothing to guarantee hygiene and
  prevention of infections.
• Safety and Security of the Hospital
• Monitor temperature, humidity, air quality.
• Identify obstacles for mobile stretchers.
• Protect access to FDA controlled products,
  narcotics, and special drugs.
• Monitor tampering with medicine, fraud in
  prescriptions.
• Protect against electromagnetic attacks, power
  outages, and discharge of biological agent.

7
Privacy and Security of Network and Computer
Systems

• Privacy of patient record and identification.
• Protect against changes to patient records or
  treatment plan.
• Protect against disabling monitoring devices,
  switching off/crashing computers, flawed
  software, disabling messages.
• QoS issues for multimedia data
• Vulnerabilities of wireless communication
  protocols such as 802.11 and bluetooth.
  Decrypting traffic, injection of new traffic,
  attacks from jamming devices.

8
Measures of Safety and Security

• Number of incidents per day in patient room,
  ward, or hospital.
• Non-emergency calls to nurses and doctors due to
  malfunctions, failures, or intrusions.
• False fire alarms, smoke detectors, pagers
  activation.
• Wrong information, data values, lost or delayed
  messages.
• Timeliness, Accuracy, Precision.

9
Conclusion

• Use of sensors can increase safety and security.
• But can be used by terrorists to kill all
  electronic, disrupt or destroy digital devices,
  and control information flow.