In addition, more children are suffering from long-term conditions such as asthma and obesity. If these people��s health could be monitored continuously over a long period of time, physicians could detect serious health problems sooner as well as provide more accurate diagnoses and better treatment. For instance, previous studies have shown that monitoring patient data can help with early detection of conditions like heart disease [1, 2]. Moreover, medical professionals could react to situations such as strokes and asthma attacks more quickly. Current monitoring solutions, however, are not suitable for long-term purpose, as patients are typically attached to a bedside device that limits their mobility and comfort.

Several research groups (e.g.

, [3, 4, 5, 6, 7]) have recently integrated medical sensors with wireless motes for health monitoring, such as the Harvard wireless pulse oximeter [4]. A mote is low-power computing device with a wireless radio; it is typically the size of a match box or even smaller. Using the motes, these medical sensors wirelessly transmit data to base stations, where it can be accessed by physicians and nurses. This frees patients from the confinement of traditional wired sensors, allowing medical professionals to monitor their health remotely over long periods. Such medical sensor networks can be deployed in hospitals, long-term care facilities, and homes. Pharmaceutical companies could also use the network to monitor patients in clinical trials in order to develop better drugs.

Moreover, the system can be extended to monitor the vital signs of people working in hazardous conditions, such as firefighters in a burning building, relief workers in a disaster area, and soldiers on a battlefield.Although medical Batimastat sensor networks are extremely useful and versatile, the medical data they collect is sensitive, and the privacy of such data is legally protected (e.g., the Health Insurance Portability and Accountability Act of 1996 (HIPAA) [8]). A patient��s Brefeldin_A physiological data may reveal what disease the patient has (which might be useful to parties such as insurance companies). As such, an attacker may profit financially by selling data obtained through eavesdropping.

Moreover, the attacker could even cause physical harm to a patient by misreporting or spoofing the patient��s data, resulting in improper diagnosis and/or treatment. Therefore, it would be irresponsible to design and deploy a medical sensor network without adequate security mechanisms. Moreover, patients will not make use of this system if they are not convinced that their data will be kept confidential, regardless of how good the system��s performance is.