Yousif Al Ridhawi

QoS-Based Composition of Service Specific Overlay Networks

Optimization of service compositions represents a challenging area of research in mobile networks. The use of formal semantic descriptions of service interfaces and functionalities enable automated reasoning over service compositions. The growing challenge of finding effective methods to satisfy non-functional QoS requirements of customers exacerbates the composition problem. Fuzzy reasoning provides an effective means to represent QoS concepts that are vague or approximate thus providing a flexible best-match service query scheme. This paper presents a new fuzzy-induced, semantic-similarity-based service-specific overlay network composition over a hybrid service overlay network. The presented composition method allows for efficient, accurate, and QoS-aware component service discovery, composition, and execution. We demonstrate that our approach provides better performance and reduced composition delay when compared to other service-composition solutions.

Service specific overlay composition and reconfiguration

This paper presents a Hybrid Service Overlay Network (H-SON) for composing Service Specific Overlay Networks (SSON) in mobile environments. The overlay topology is organized into dynamically-adaptable hierarchical Chord rings reflecting node mobility and service quality transformation. Moreover, our loss-based utility function is used to predict the clients QoE. Node resources can thus be automatically and dynamically redistributed and established SSONs can be reconfigured before quality levels deteriorate below acceptable levels. The proposed H-SON can accelerate the composition process by limiting service searches into bounded areas and can limit query broadcasts.

A context-aware and location prediction framework for dynamic environments

Context based dynamic adaptation of autonomous services and applications require the acquisition of an array of contextual information. Context dissemination mechanisms may result in network flooding, unrestricted access to private context information, and the inability of consumers to limit or personalize received context. Adapting context information disseminated to users is linked to direct contextual requests made by users. This paper describes policy- and ontology-based, context-aware system architecture. A Context Level Agreements is proposed to help deliver contextual information to users according to their needs. The paper illustrates use of the negotiation protocol through design and implementation of context-aware system architecture capable of acquiring, modeling, reasoning and disseminating context through ontologies.

Workflow-Net Based Service Composition Using Mobile Edge Nodes

Content delivery through cloud networks has gained popularity due to the cloud’s ability to provide on-demand services. However, composite services, such as customized multimedia content, introduce both delays and resource limitations if traditional cloud solutions are used. With recent advances in mobile edge computing, customized media delivery can be achieved through compositions of service specific overlays (SSOs). This paper presents a workflow-net-based mechanism for mobile edge node cooperation in fog-cloud networks to form guaranteed SSOs. The proposed solution uses a mathematical cooperation operator to turn the SSO composition problem expressed as workflow nets into algebraic representations. In turn, the minimal cost cooperative path from the workflow net is determined such that it guarantees the delivery of the requested composite media services to clients. Experimental results show that the composition process can be adequately established and carried out in a timely manner.

Policy-Based Personalized Context Dissemination for Location-Aware Services

This paper presents a policy-based context-level negotiation protocol and context-aware system architecture to personalize consumer-received context information through negotiations. Location tracking and prediction empower the system to shape contextual information delivered to users according to their expected needs.

An Adaptive Vertical Handover in Service Specific Overlay Networks

This paper proposes a new vertical handover (VHO)-enhanced mobile service discovery and composition method over a hybrid service overlay network (H-SON). The overlay considers the dynamic characteristics of mobile nodes in the decision for node placement as well as the types of services provided and Quality of Service (QoS) levels. The mobile nature of media clients provokes a necessity to consider VHO operations to meet the requirements of offered service level agreements (SLAs). The integrated framework continuously derives optimal VHO configuration policies with respect to handover initiation and network selection for service specific overlay network (SSON) node migration. The VHO-enhanced service composition method allows for efficient, accurate, and QoS-aware component service discovery, composition, and execution. We demonstrate that our approach provides better performance and reduced composition delay in heterogeneous network environments when compared to other service-composition solutions.

An architecture for autonomie management of overlay networks

Recent efforts in service composition has led to an increase in the number of available services on the Internet. As a result, networks became more service centric. The heterogeneity of network components and access technologies made the management of these services more complex and time consuming. In an effort to ease the management of Service Specific Overlay Networks (SSON), we propose a new architecture which exploits the use of overlays to hide the complexities in the network infrastructure while supporting the service specific management. The proposed architecture is designed to integrate autonomie principles in order to facilitate the management of networks with minimal human intervention. It proposes the use of SSON on top of the overlay network to deliver the services users request through a hybrid overlay structure. The proposed architecture also includes a utility-based feedback mechanism to monitor the Quality of Experience (QoE) of services in order to ensure that service providers meet the quality expectations of users. Simulation results indicate a significant improvement in terms of node joining delay and overhead compared to current technique.