An Energy Efficient Protocol Architecture for m-Health Systems Stefano Tennina ‡ , Elli Kartsakli ∗ , Fabio Graziosi ‡ , Manuel Santos ‡ , Aris S. Lalos ∗ , Angelos Antonopoulos ‡‡ , Prodromos-Vasileios Mekikis ∗ , Marco Di Renzo § , Luis Alonso ∗ and Christos Verikoukis ‡‡ ‡ WEST Aquila srl, University of L’Aquila, Italy ∗ Signal Theory and Communications Dept., Technical University of Catalonia (UPC), Barcelona, Spain § Laboratory of Signals and Systems (L2S), University Paris-Sud (Paris), France ‡ Telecommunications Technological Centre of Catalonia e-mail: {tennina, manuel.santos, fabio.graziosi}@westaquila.com, marco.direnzo@lss.supelec.fr, {ellik, aristeidis.lalos, vmekikis, luisg}@tsc.upc.edu {cveri,aantopoulos}@cttc.es Abstract—Contemporary technologies as implemented in the field of health care have provided the everyday clinical practice with a plethora of tools to be used in various settings. However, from all established and emerging applications, priority will be given to those amongst them that target problems pertinent to efficiency in health care delivery that is also associated with in- creased costs tantalizing contemporary National Health Systems (NHS) not only in Europe but globally. In this field, WSN4QoL is a Marie Curie project which involves academic and industrial partners from three EU countries, which aims to propose new Wireless Sensor Networks (WSNs)-based technologies to meet the specific requirements of pervasive healthcare applications. This paper focuses on presenting a protocol stack architecture designed to support the solutions proposed in that project to enhance energy efficiency. I. I NTRODUCTION e-Health, according to Health Information and Management Systems Society (HIMSS) is defined as “the application of In- ternet and other related technologies in the healthcare industry to improve the access, efficiency, effectiveness, and quality of clinical and business processes utilized by healthcare orga- nizations, practitioners, patients, and consumers to improve the health status of patients”. Recently a sub-segment of e- Health has emerged. This field is called m-Health, where m indicates the use of mobile communications and one of the definitions provided by Professor Robert Istepanian is “the use of emerging mobile communications and network technologies for healthcare” [1]. In 2010, the m-Health Summit of the Foundation of the National Institutes of Health came up with yet another definition this time shifting the weight of implementation to the devices: “the delivery of healthcare services via mobile communication devices” [2]. In the current document the terms e-Health and m-Health will be used interchangeably as the focus of the project lies in the field of wireless and mobile communications. m-Health is not a surrogate for the clinician. It does provide the means to extend the reach of the provider beyond a face- to-face patient encounter, with the advantage of expanding the delivery of limited resources and expertise. For instance, using electronic images and pictures, diagnoses may be made from a remote location, either within or outside the facility. The m-Health Systems Architecture includes several dimensions that can be materialised according to the specific environment: (i) Internet: access to information and sites with adequate access privileges per user category (doctors, nurses, admin- istration, etc.) or universal access to public content such as education material with epidemiological characteristics (e.g., information on human papillomavirus or immunodeficiency virus, tuberculosis, etc.). (ii) Extranet: secure, remote connec- tions between predefined participants (links between primary, secondary and tertiary health care levels) even including e- commerce (enterprise resource planning ERP systems). (iii) In- tranet: communications infrastructure within the enterprise, which may facilitate and deliver access to internal and core data systems to all participants in the healthcare delivery chain. (iv) Core Data Systems: function-based systems that support the key processes of the enterprise. These may be financial, clinical or administrative systems. Included in this group are systems such as the electronic health record (EHR), Diagnostic Support Systems (DSS), admission and appointment systems, financial patient accounting systems as well as the internal infrastructure systems. (v) Telecommunications: the physical and technical layer that enables the connections and inter- change of information through all available media: wireless, fiber, cable, satellite, and any other new and emerging means. Voice and email are interchangeable on some of the new devices. Recording, storing and transmitting this information falls within the boundaries of m-Health. (vi) Hardware: com- puters, pagers, personal digital assistants (PDA’s), PC tablets telephones, servers and a plethora of vital signs capturing sensors to be used in conjunction with the DSS provide the physical support for this infrastructure. The m-Health environment is provided by the relatively seamless interaction of these layers permitting the exchange of information and transactions. The rapid development of new technologies is also reflected in the adoption of many tools from all telecommunication fields, often significantly less expensive than the prior generations. New technologies are easily integrated into existing scenar- ios when they address issues not yet resolved under the current implementations. Contemporary m-Health reality consists of an amalgam of sensors targeting to measure or assess an individual’s vital signs or even to track his/her location in case