Khalid Elgazzar

Clustering WSDL Documents to Bootstrap the Discovery of Web Services

The increasing use of the Web for everyday tasks is making Web services an essential part of the Internet customers daily life. Users query the Internet for a required Web service and get back a set of Web services that may or may not satisfy their request. To get the most relevant Web services that fulfill the users request, the user has to construct the request using the keywords that best describe the users objective and match correctly with the Web Service name or location. Clustering Web services based on function similarities would greatly boost the ability of Web services search engines to retrieve the most relevant Web services. This paper proposes a novel technique to mine Web Service Description Language (WSDL) documents and cluster them into functionally similar Web service groups. The application of our approach to real Web services description files has shown good performance for clustering Web services based on function similarity, as a predecessor step to retrieving the relevant Web services for a user request by search engines.

Ubiquitous Health Monitoring Using Mobile Web Services

The ever-increasing rise in the number of chronically ill people is a growing burden on healthcare institutions. People with chronic illnesses such as heart disease, being among the leading causes for morbidity and mortality, need constant monitoring of their health conditions. Remote health monitoring of patients residing in their homes helps reduce healthcare costs. Current telemedicine solutions are used to remotely monitor vital signs such as blood pressure and blood sugar levels. These systems restrict the mobility of the patient, in addition to being limited in the number of vital signs that they support. The rapid developments in mobile devices coupled with the advancements in wireless access technologies have made mobile devices an increasingly attractive platform for delivering remote patient health monitoring services. This paper demonstrates the capability of mobile devices to provide mobile, low-cost, and efficient remote health monitoring through a mobile Web services-based approach. The proposed approach shows an agile, flexible, interoperable, and economical alternative to existing remote health monitoring systems. c � 2012 Published by Elsevier Ltd.

Effective Web service discovery in mobile environments

Recent advancements in the design of mobile devices and wireless technologies have produced a successful coupling of mobile devices and Web services, where mobile devices can be a service provider or a consumer. However, finding relevant Web services that match requests remain a major hindrance to its booming. The challenges facing Web service discovery are further magnified by the stringent constraints of mobile devices, and the inherit complexity of wireless heterogeneous networks. While significant research has focused on service discovery protocols in isolation, they mostly lack a holistic capacity to address the different limitations collectively. We introduce a novel discovery framework that addresses all aspects of mobile Web service discovery, yet does not jeopardize the efficiency requirement for this discovery; especially as an application run in resource-constrained environments.

A Framework for Efficient Web Services Provisioning in Mobile Environments

Advancements in wireless networks and mobile device capabilities enable ubiquitous access for Web resources anywhere anytime. Web service technologies enable rapid and low-cost development of networked and portable applications. The successful convergence of these technologies produces mobile Web services provisioning, where mobile devices can host and provide Web services. However, the resource constraints of mobile devices and the characteristics of wireless networks pose key challenges to mobile Web services provisioning. Several research efforts have studied the Web services provisioning from mobile devices, however, they address specific aspects in isolation which may yield inefficient Web service provisioning. This paper proposes a generic framework for efficient Web services provisioning in mobile heterogeneous environments with resource-constrained mobile devices. We demonstrate the proposed framework using a use-case scenario and a sample prototype. A preliminary provisioning prototype shows that the framework is able to provide reliable and personalized Web services while maintaining the service availability.

Comparing uplink schedulers for LTE

The choice of SC-FDMA for uplink access in Long Term Evolution (LTE) facilitates great flexibility in allocating medium resources to users while adapting to medium condition. A multicarrier multiple access technique, SC-FDMA gains an advantage over OFDMA in that it reduces the energy requirements in user equipment. 3GPP Releases 8 and 9, however, do not detail a specific scheduler and, accordingly, proposals have been made in the literature in designing an efficient and capable uplink scheduler for LTE. This paper presents a preliminary performance evaluation for representative proposals, and offers medium of comparison in order to highlight the individual characteristics of each proposals.

Cloud-Assisted Computation Offloading to Support Mobile Services

The widespread use and increasing capabilities of mobiles devices are making them a viable platform for offering mobile services. However, the increasing resource demands of mobile services and the inherent constraints of mobile devices limit the quality and type of functionality that can be offered, preventing mobile devices from exploiting their full potential as reliable service providers. Computation offloading offers mobile devices the opportunity to transfer resource-intensive computations to more resourcefulcomputing infrastructures. We present a framework for cloud-assisted mobile service provisioning to assist mobile devices in delivering reliable services. The framework supports dynamic offloading based on the resource status of mobile systems and current network conditions, while satisfying the user-defined energy constraints. It also enables the mobile provider to delegate the cloud infrastructure to forward the service response directly to the user when no further processing is required by the provider. Performance evaluation shows up to 6x latency improvement for computation-intensive services that do not require large data transfer. Experiments show that the operation of the cloud-assisted service provisioning framework does not pose significant overhead on mobile resources, yet it offers robust and efficient computation offloading.

AppaaS: offering mobile applications as a cloud service

With the huge number of offerings in the mobile application market, the choice of mobile applications that best fit particular objectives is challenging. Therefore, there is a demand for a platform elevating the momentum of mobile applications that can adapt their behavior according to the user’s context. This paper proposes AppaaS, a context-aware platform that provides mobile applications as a service. AppaaS uses several types of context information including location information, user profile, device profile, user ratings, and time to provision the best relevant mobile applications to such a context. AppaaS supports state preservation, where user-specific data and application status are stored for the user’s future reference. Experimental validation demonstrates that AppaaS alleviates the burden on mobile users to find applications that work best for a particular situation. It also enables application providers to dynamically control access to the functionality of their applications. Performance evaluation results show that AppaaS can employ cloud elastic resource provisioning to offer flexible scalability, while satisfying certain QoS constraints. Experimental results also support a conclusion that with little overhead handling context information, AppaaS can bring remarkable benefits to provisioning mobile applications as a service.

goDiscovery: Web Service Discovery Made Efficient

The growing popularity of cloud computing has magnified the rise of software reuse by facilitating service provisioning over the Internet. At the same time, a new generation of mobile apps has emerged relying on backend services that expand the app functionally, while reducing the overhead on limited mobile resources. The Web service approach promises great flexibility in offering software functionality over the network, while maintaining interoperability between heterogeneous platforms. In addition, recent years have witnessed the rise of user-facing service developments that can be consumed on-the-go with a standard interface, such as Restful Web services. However, the discovery of such services does not match their growing popularity and remain challenging. Users cannot tolerate long latency in finding relevant services to their requests. In this paper, we propose a robust and efficient Web service discovery approach that uses statistical methods and indexing techniques to improve the precision and response time of the discovery process. Experimental results demonstrate that the proposed approach outperforms the state-of-the-art discovery mechanisms and significantly reduces the query response time by at least 77%, while maintaining comparable accuracy.

Empowering Mobile Service Provisioning through Cloud Assistance

The use of mobile devices as data service providers is on the rise. Mobile devices feature a large set of distinct characteristics that qualify them to be the most convenient computing platform for online services, both as consumers and providers. Mobile devices can take advantage of their mobility to provide location-based services and their association to a specific user to customize service offerings to fit personal preferences and current conditions. However, the increasing resource demands of mobile services and the inherent constraints of mobile devices limit the quality and type of functionality that can be offered, preventing mobile devices from exploiting their full potential as reliable data providers. Cloud computing offers mobile devices the opportunity to run resource-intensive tasks through computation offloading. The offloading decision is a tradeoff between data transfer and latency improvement to the benefit of alleviating the burden on mobile resource while improving the overall performance of service provisioning. This paper presents a framework for cloud-assisted mobile service provisioning, aimed at offering an augmented environment to resource-constrained mobile providers in order to deliver reliable services. The framework supports dynamic offloading based on the resource status at the mobile side and current network condition as well as user-defined energy constraints. It also enables the mobile provider to delegate the cloud to forward the service response directly to the user, given that no further processing is required by the provider. Performance evaluation shows up to 6x latency improvement for computational-intensive services that do not require large data transfer.

RobP2P: A Robust Architecture for Resource Sharing in Mobile Peer-to-Peer Networks

Peer-to-peer (P2P) systems are constructed to provide resource sharing among interested participants (peers) in a distributed and self-organized fashion. The way P2P networks are formed is critical to the overall system performance due to communications and network maintenance overhead. Mobile environments pose additional challenges on P2P networks due to heterogeneity of nodes, inherent limited resources, dynamic context and wireless network characteristics. This paper presents RobP2P, a robust architecture to construct mobile P2P networks and efficiently maintain the network state. RobP2P introduces a novel super-peer selection protocol based on an aggregate utility function that takes into account peers’ capability and context. It also presents an agile scheme through which super-peers can delegate their responsibilities to more powerful and stable joining or existing peers. Our simulation results show that the RobP2P is efficient, less prone to failure, and generates lower overhead traffic, while reliably maintaining the consistency of network state . c