Privacy aware key establishment for publish/subscribe infrastructures in Ubiquitous environments

Ubiquitous Computing, UbiComp, is a vision of embedding computing to every aspect of our day to day life. In ubiquitous computing, interaction among communicating entities exists in highly dynamic, large scale and failure prone environments. Publish/Subscribe interaction paradigm, Pub/Sub, can be used to decouple interacting entities in ubiquitous environments by delivering events based on users interests. In this scenario, securing events dissemination and protecting users' privacy are essential requirements for ubiquitous applications. In this thesis, we propose an encryption key establishment scheme for encrypting disseminated events in ubiquitous Pub/Sub infrastructures. The proposed key establishment scheme considers the dynamism, scalability and failure tolerance issues of ubiquitous environments. More importantly, the generated encryption keys reflect multi level access control polices, which is important to enforce users' privacy polices

Routing Protocols for Wireless Ad Hoc Wireless Networks: A Review of the On-Demand Routing Protocols.

Wireless Ad hoc networks have thier own very specific features. They have dynamically changing topologies, along with relatively limited resources of the transmission medium and the mobile nodes. On demand routing protocols were introduced to adapt with these features of the ad hoc network. This paper reviews this class of protocols. The highly dynamic nature of the wireless ad hoc networks imposes it own requirements on proposed routing protocols for this type of networks. At the same time, on-deman

Supporting Distance Vector Routing Over Device Discovery Flows in the Pervasive Middleware PalCom

PalCom is a pervasive middleware that enables users to combine services from different devices into assemblies, or usage scenarios. The mechanism of device discovery in PalCom builds an ad-hoc network of interconnected devices while replacing cross-network periodic keep-alive messages with timely forwarded events that notify devices about the discovery and undiscovery of each other. Moreover, the device discovery mechanism is decoupled from any specific routing decisions mechanism. In this paper, we present a design that builds on this flexibility to add distance vector routing to PalCom while inheriting the event based cross-network device discovery for updating routing tables on interacting devices. The proposed design has been implemented and evaluated against a network with links that continuously change their availability

Device discovery for the PalCom pervasive middleware with eliminated cross-networks periodic heart-beat messages

Service discovery is central in pervasive middleware systems, built on top of the communication substrate using the more fundamental mechanisms for device discovery. In mobile pervasive systems devices come and go, and switch network frequently, demanding support for device discovery across heterogeneous networks. We present the design of a device discovery mechanism for the PalCom middleware that eliminates the need for cross-network periodic keep-alive messages while still supporting timely detection of missing devices, i.e. undiscovery. The design has been implemented and is evaluated against the simplistic approach of flooding the inter-connected networks with keep-alive messages. (C) 2014 The Authors. Published by Elsevier B.V

Media Abstraction Framework for the Pervasive Middleware PalCom

Pervasive middleware systems are important for enabling the configuration and coordination of the services provided by devices in pervasive environments. PalCom is an example of such a system that aims to enable interaction among pervasive services over heterogeneous networks. In this paper we discuss the need for providing networking-media independent messaging among pervasive devices, and identify the problem of designing a media abstraction framework for a pervasive middleware. We identify a number of design principles and features that need to be satisfied by such a framework. The most important of these principles is the separation of networking protocol aspects into abstraction representations, which are exposed in a unified format to upper layers of PalCom, and communication mechanisms which are hidden by media-specific implementations of our proposed media-abstraction framework for PalCom. Also, we explain our implementation and evaluation of that framework

Synchronizing Device Discovery on Loss of Update Messages in the Pervasive Middleware Palcom

PalCom is a pervasive middleware that enables users to combine the services on devices into useful configurations. Interconnected PalCom devices can discover, and keep track of, the existence of each other by exchanging periodic heartbeats within local networks, and once-sent device appearance/disappearance notifications across interconnected networks. This approach has the advantage of eliminating the need to forward periodic heartbeats beyond the boundaries of the local networks of their originator devices. However, when a device appearance/disappearance notification is sent only once over an unreliable channel, there is a possibility of losing that notification. As a result, the device discovery information on PalCom devices will be out-of-sync. In this paper, we present the design, model-based evaluation, and the implementation status of a solution to this synchronization problem