gms | German Medical Science

Computer users are used to typing in usernames and passwords to protect their sensitive computer applications. Usually every single application requires a different password. Thus people tend to be very creative to keep track of their password, often with the disadvantage, that they are not secure any more. Furthermore, passwords can easily be guessed or cracked [Ref. 1], [Ref. 2]. Protecting a Personal Health Record with a username and a password only does not seem to be a good idea. Unfortunately, that's the way how most of today's electronic health record systems are protected [Ref. 3], [Ref. 4], [Ref. 5], [Ref. 6], [Ref. 7], [Ref. 8], [Ref. 9], [Ref. 10].

Strong authentication makes use of the "techniques that permit entities to provide evidence that they know a particular secret without revealing the secret". The most well known strong authentication system is pubic key encryption and the related Public Key Infrastructure (PKI) to ensure identity of the users [Ref. 11]. Each user's public key is published in a directory, whereas the private key has to be stored on a secure device like a smartcard. Other tokens could be a key file, crypto hardware, USB-Dongle or a subscriber identity module (SIM) equipped cell phone.

Advanced Personal Health Records need strong authentication, as the records may contain more sensitive information than any hospital record[Ref. 5]. Future implementations will even contain genomic data of patients [Ref. 12], [Ref. 13] the patient as record owner will be able to annotate the data [Ref. 9]. Secondly these records will be used anywhere - not predominantly in a trustworthy environment.

Achieving a balance between providing the necessary security, while promoting user acceptance, is a major obstacle in large-scale deployment of PHRs.

Strong authentication with standard PKI components generally meets the demands, but the traditional tokens and the corresponding equipment are hard to deploy in an inhomogeneous environment. Furthermore the acceptance of additional tokens is generally bad [Ref. 14], [Ref. 15]. These tokens have to be deployed, need additional hardware like card readers and additional software like hardware drivers.

Wireless authentication with cell phones could redundantize the deployment of personal tokens and raise acceptance for strong security measures. Albeit standard cell phones can only be used to some degree for wireless authentication, new third generation (3G) cell phones together with a mobile authentication service could meet all the demands of strong authentication and achieve user acceptance.

Cell phone authentication offers interesting possibilities for patients and medical staff to access patient data, which would not be disclosed without strong authentication.

We see a necessity of strong authentication especially in the usage of PHRs in insecure environments. USIM-equipped cell phones could be useful devices for healthcare-related applications requiring strong authentication. Nevertheless there are several problems to be addressed in future investigations. They mainly arise from the need for usability and high availability including the registration process, the Mobile Authentication Service, the lag time and the evaluation.

Due to the shortcomings of authentication methods based on SIM-equipped devices [Ref. 16], [Ref. 17] we should build strong authentication capabilities using USIM-based 3G mobile equipment [Ref. 18].

Cell phone-mediated authentication provides the security strength of PKI and avoids the problems that traditionally plague the PKI implementations. Therefore strong authentication via mobile equipment has potential to provide strong authentication in health care.