An Architecture for M2M Enabled Social Networks

Social Networks (SNs), such as Facebook, Twitter, Google+, are becoming more and more popular nowadays. People are now more connected than before. They share information, pictures, videos and news with their family and friends. However, sharing physical phenomena in SNs is still a manual process done by people themselves. For instance, people would like to share current health status, feelings, thoughts, weather or riding information with friends. The sharing of ambient information automatically in SNs can promote independent living. Moreover, it can enhance the autonomy and confidence of elderly people via continuous monitoring and health support. A set of biometric sensors, for example, placed within a patient body can inform a doctor about patient’s health status; hence the doctor can perform a remote diagnosis. Nowadays people are surrounded by devices like smartphone, sensors, cameras, computers and many other devices known as machines. These devices can automatically collect contextual information from the neighborhood. This thesis proposes an architecture for posting contextual information in SNs to support the automatic sharing of physical phenomena. In the proposed architecture, machines collect the contextual data through an overlay-based gateway to support scalability in terms of number of devices. Considering the resource-constrained devices, the architecture makes use of the Constrained Application Protocol (CoAP), a lightweight standard protocol. An SN processes that data into shareable information and disseminates it as appropriate within the users’ Community of Interests (COIs) (e.g., family, friends). A proof of concept prototype is developed to verify the feasibility of the proposed architecture and its performance has been partially evaluated

Registry composition in ambient networks

Ambient Networks (AN) is a new networking concept for beyond 3G. It is a product of the European Union's Sixth Framework Program (FP6). Network composition is a core concept of ANs. It allows dynamic, scalable and uniform cooperation between heterogeneous networks. ANs can host various registries. These registries may be of different types (e.g. centralized, distributed), store heterogeneous types of information (e.g. raw data vs. aggregated data), and rely on different interfaces to access the stored information (i.e. protocols or programming interfaces). When ANs compose, the hosted registries need to compose. Registry composition is a sub-process of network composition. It provides seamless and autonomous access to the content of all of the registries in the composed network. This thesis proposes a new architecture for registry composition in ANs. This overall architecture is made up of four components: interface interworking, data interworking, negotiation and signaling. Interface interworking enables dynamic intercommunication between registries with heterogeneous interfaces. Data interworking involves dynamically overcoming data heterogeneity (e.g. format and granularity). Interface and data interworking go beyond static interworking using gateways, as done today. The negotiation component allows the negotiation of the composition agreement. Signaling coordinates and regulates the negotiation and the execution of the composition agreement. Requirements are derived and related work is reviewed. We propose a new functional entity and a new procedure to orchestrate the composition process. We also propose a new architecture for interface interworking, based on a peer to peer overlay network. We have built a proof-of-concept prototype. The interface-interworking component is used as the basis of our new architecture to data interworking. This architecture reuses mechanisms and algorithms from the federated data base area. The thesis proposes as well a new architecture for on-line negotiation. The architecture includes a template for composition agreement proposals, and a negotiation protocol that was validated using SPIN. A new signaling framework is also proposed. It is based on the IETF Next Step in Signaling (NSIS) framework and was validated using OPNET. Most of these contributions are now part of the AN concept, as defined by the European Union's Sixth Framework Progra

Signaling for conferencing in mobile ad hoc networks

Mobile Ad hoc NETworks (MANETs) are networks that do not need to be pre-configured. They are composed of transient nodes connected through wireless interfaces. Due to their flexibility, the ease to build and the associated low cost, they are gaining more and more momentum. They are also seen as part of the fourth generation wireless networks. New applications, such as conferencing, are emerging for such networks. Conferencing enables a set of applications such as audio/video conferencing, debating, distance-learning and multi-party gaming. The implementation of conferencing in MANETs is not an easy task due to scarce network resources, heterogeneous devices, frequently changing topology and unstable wireless connections. It challenges each technical aspect of conferencing: signaling, media handling and conference control. Signaling is the control component of conferencing. It handles the session initiation, modification and termination. In this work, we focus on signaling for conferencing in MANETs. Two types of MANETs are considered: standalone MANETs and integrated MANETs/3G networks. Background information is provided, requirements are derived and the state of the art, including signaling protocols such as SIP and H.323, are reviewed. Since there is no existing solution that meets all of the derived requirements, we propose a novel cluster-based signaling architecture that meets the requirements of signaling for standalone MANETs. The clusters are application-layer clusters that are dynamically created and deleted for a conference. We also propose a signaling architectures for integrated MANETs/3G networks. The solution is based on conference gateways. We implement the architectures using SIP extensions. Experimental results are obtained from prototypes and OPNET based simulations. In the prototype, we built the signaling system on a small scale network using IEEE 802.11 ad hoc settings. In the OPNET simulation, we use MANET features. From experiments, we found that clustering is a very promising approach for solving signaling problems in MANETs. Being aware of several performance issues of our signaling systems, we further propose optimization schemes that are based on cross-layer design. We also implement some of these schemes and apply them to our signaling systems. The evaluation shows that the schemes significantly improve the signaling performance