1. Introduction
Remote medical monitoring, particularly of people with chronic diseases such as congestive heart failure or Alzheimer's, is widely viewed as a critical technological innovation for reducing health care delivery costs and improving the responsiveness of medical care. Our focus in this paper is on improving the operational efficiency of the so-called 3-tier remote monitoring architecture [1], [2], where an open, standards-based personal gateway device (such as a PDA or smart phone) is interposed between the body-worn biomedical sensors and the remote backend infrastructure. The gateway device connects to the sensors via a short-range Body Area Network (BAN) technology (e.g., Bluetooth™ or ZigBee™), and uses a second wide-area (WAN) interface (e.g., GPRS or 802.11) to transport the collected sensor data to the backend infrastructure.