locks (elemen- tary roles), but change which are combined together and in which order they are executed. Further details of this layer may be found in Rossebo et al. [10]. A family of services will run dynamically in the system, according to a global PESM description and policy rules. But additionally, the policy rules and PESM diagrams may be changed by a central administrator. Changes made centrally are then distributed to the different parts of the system, and in this way services may be dynamically adapted and changed. Additionally, in the system, a system security policy, such as an availability policy may be violated causing a need to dynamically adapt the service. In such a case, the system would look up in a repository, the appropriate PESM and policies to apply. For example, if the management system registers X maxlimit, the number of unauthorized uses of the service exceeds the limit of such unauthorized behavior allowed by the availability management policy; this may trigger the requirement for stronger authentication to gain access to the service. In this case, the service must be dynamically adapted and composed with a sufficiently strong authentication pattern. Depending on which policy rules are satisfied, different authentication patterns will be called. Service Delivery Platforms 5.3 Description of the Tele-Consultation Service The tele-consultation system is designed to allow chronically ill patients to have intermediate consultations from their homes, SO as to reduce repeated travel to the doctor's office/hospital for routine consultations when routine tests may be equally well performed remotely. Equipment is provided in the home for carrying out tests. This equipment collects data from, for example, medical sensors and this informa- tion is transmitted/communicated to the doctor. In order to request a consultation with a doctor, the patient needs to register to an electronic tele-consultation service desk, which then sets up a remote consultation with the patient's doctor, depending on availa