Semantic Handover among Distributed Coverage Zones for an Ambient Continuous Service Session

Abstract

In a user-centric approach, the end-user wants the best Quality of Experience (QoE) and the highest context-awareness. Throughout end-user’s spatial mobility, service providers must continuously adapt the end-user’s service session according to his or her new ambient context, without neglecting functional preferences and demanded Quality of Service (QoS). Many spatial mobility management solutions have been conceived to help operators managing the network part of their end-users’ sessions. However, this problem is not yet investigated on the service layer. For this purpose, the authors propose in this paper the concept of semantic handover. This concept acts on the service layer by analogy to the network’s handover mechanisms. It is based on three complementary roles: the initiator, that detects a spatial mobility and initiates the semantic handover; the decider, that decides which services should be replaced in the end-user’s service session and what are their ubiquitous ambient counterparts; and the executor, that executes the decision and adapts the end-user’s service session to the new ambient context. This solution is based on highly scalable distributed coverage zones. Service providers must deploy their ubiquitous services, having the same functionality and an equivalent QoS, in different geographic areas, and they must associate each service to a specific coverage zone. Therefore, when the end-user moves among coverage zones, a semantic handover is launched to guarantee seamless service continuity throughout end-user’s ambient contexts.