The continuously increasing Internet coverage and its availability has give rise to an issue that was once considered not important to take into consideration. Today a number of applications use the Internet to de-liver time critical messages. The usage of wireless Access Points involves a considerable percentage to connect mobile devices to the Internet pro-vider. However, these relatively cheaper Internet Access Points have their own disadvantages as compared to the GSM and ADSL. The access points cover a very limited area and thus in order to cover a wider area multiple access points must needs to be installed. In other words, as the user moves he/she is supposed to switch between access points. Never-theless, the basic problem in such cases is involves packet loss during handover. In today’s technological advancements these issues, though very small, are no more insignificant but are required to be handled prop-erly. So protocols such as MobileIP, LISP, HOST have been proposed and are currently being used for such a purpose. Furthermore, in this thesis a mechanism to reduce such packet losses has been studied and proposed in relation to the SensibleThings Internet-of-things platform. A workaround solution known as Mobile DCXP has been proposed and implemented and comparisons with the existing system have been carried out. In addition, a generic solution has been discussed in detail and compared with the Mobile DCXP. However, the implementation of the generic solution has been deferred to the future. The concept of Mobile DCXP has been illustrated with proof-of-concept apps and an implementation of a simple Android Application known as IChat has been conduct. The IChat is a simple chat app that is used in the experi-ment to determine out the packet lost during handover and to carry out a comparison. Finally, based on the data collected from IChat, an evaluation of Mobile DCXP has been presented and a performance comparison with Mobile Proxy DCXP has been illustrated with charts. Furthermore, in the conclusion Mobile DCXP could minimize packet loss as compared to the existing system.

The current paradigm shift in computing has placed mobile computation at the centre of focus. Users are now even more connected; demanding everything everywhere services. These services, such as social networking and media, benefit from the availability of context information seamlessly gathered and shared; providing customized and user-centric experiences. The distribution of context information no longer conforms to the paradigms of the existing Internet with regards to heterogeneity, connectivity and availability. This mandates new approaches towards its organization and provisioning in support of dependent applications and services. In response to these developments, the work summarized in this thesis addresses the fundamental problem of presenting context information in organized models as relevant subsets of global information. In approaching this problem, I introduced a distributed collection of context objects that can be arranged into simple relevant subsets called context schemata and presented to applications and services in supporting the realization of context based user experiences. Acknowledging the dynamic behaviour inherent of the real world interactions, I introduced an algorithm for measuring the proximities and similarities among these context objects, providing a metric through which to achieve organization. Additionally, I provided a means of ranking heterogeneous and distributed sensors in response to real time interaction between users and their digital ecosystem. Ranking provides an additional metric with which to achieve organization or identifying important and reputable information sources. The work I present here, additionally details my approach to realizing this complete behaviour an a distributed overlay, exploiting its properties for distribution, persistence and messaging. The overlay is also utilized for the provisioning of the supporting context information. Improvements in the ability to discover and attach new context information sources is fundamental to the ability to continually maintain expressions of context, derived from heterogeneous and disparate sources. By being able to create relevant subsets of organized data related to the requirements of applications and services in an end-point, infrastructures are realized for connecting and supporting the increasingly large numbers of users and their sources of information. Coupled with the distribution, these infrastructures realize improvements with regards to the effort required to achieve the same results. The culmination of the work presented in this thesis is an effort to enable seamless context-centric solutions on a future Internet of Things and thus constituting an adequate solution to the challenges raised above.

This thesis was prepared in collaboration with Acreo (Research and Development Company) and OpenCare (IT Company). Its purpose was to design and develop a research testbed to enable context awareness in pervasive environments by modifying the MediaSense framework (EU Funded project) of Mid Sweden University. In ubiquitous environments, the proliferation of devices such as sensors, active badges, mobile phones, RFID and NfC tags enables the development of intelligent services towards new forms of pervasive applications. These intelligent services seamlessly gather context information and the benefits offered are in the provision of better services. The inspiration given by these intelligent services has meant that the focus of thesis has been on using these services in a healthcare application. The challenge is that the proposed testbed should address the intelligent delivery of health information to any host, anywhere, based on the user’s context. Further, context reasoning requires substantial computing power and smart devices have limited resources in terms of processing and memory, so, the testbed should enable smart communication to take place between these devices. The proposed solution satisfies the stated requirements by using a cloud infrastructure and a Distributed Context eXchange Protocol (DCXP). Any device on the internet that is DCXP capable may register with the architecture and share context information in an efficient way. In order to view context information, TV, smartphones, internet tablets and web interfaces have been provided for both the user and the health centre. By successfully addressing the requirements of the testbed, this thesis has enabled the creation of a pervasive healthcare application. Hence, this thesis concludes with the observation that the proposed approach for context awareness in a healthcare system has the ability to deal with the stated challenges.