Ambient intelligence environment contains a large number of devices, services and applications which govern specific tasks to assist end-users. Each service domain has itself policy and managing such environments needs policies to determine suitable behavior to certain events. Policies are the way of specifying and influencing management behavior within a system, without coding the behavior into the manager agents. Typically, policy-based management systems use some form of authorization and obligation policies to guide system behavior. Obligation  policies  specify  what  actions  an  entity  must  or must  not  perform  on  the  occurrence  of  an  event. Whereas, authorization policies specify  what  actions  an  entity  can  or cannot  perform  on  the  occurrence  of  an  event.

Increasing ambient services may increase the number of users in joint areas of several domains simultaneously. These individuals will encounter unasked services which are sent by different domains in different policy patterns. In such conditions the role of policy conflict resolution and also service sending management is very important. Figure 1 shows two nested service domains with two different policies. The users locating in overlapped area are influenced by P1 and P2 services simultaneously. Consequently, conflicts will appear.

Since a considerable percent of ambient services is allocated to the information services, so this paper focuses on these kinds of services which their aim is sending services to the users with the same priority. Thus it is possible to resolve the conflicts by adopting user context independent policies. The goal of this paper is to present spatially Event-Condition-Action (ECA) policies to resolve the conflicts of such users. These policies specify the actions to be performed when a certain event occurs and the specified condition is satisfied. Since each of users has itself contexts (i.e., location, speed, direction,..), so changes in these contexts leads to experience different spatial events. In this paper, spatial events including inside, entering/ leaving, accessibility and influenceability are considered. In our opinion, a spatial relation can be considered the equivalent of a spatial event. Consequently, spatial topology relations between the user and near service sites are surveyed. Finally according to the defined policies it will be decided which is the best composition of services for him/her?. In order to implement the proposed approach an area was considered consisting two nested domains. The first domain sends information services to the users within a 300-meter radius of a hospital. The second domain sends information including entertainment attraction, rides, accommodation of passengers and parking-place to the users within a 250-meter radius of a theme park which is located near the hospital. Then based on the event based policies, sent services to the users. The results show that 75 percent of the users were satisfied by the proposed services.