• Issue 1 (2010)

Adaptive Scheduling of Message Carrying in a Pigeon Network

JUSPN, volume-01 , Issue 1 (2010), PP 39 - 48

Published: 22 Apr 2011

DOI: 10.5383/JUSPN.01.01.005

by Jiazhen Zhou a, Jiang Li , Kenneth Mitchell from Department of Systems and Computer Science Howard University, Washington DC, 20059 Department of Computer Science Electrical Engineering University of Missouri -Kansas City 64110

Abstract: The Low-Power Wireless Personal Area Networks (LoWPANs) have been recognized as a promising technology for ubiquitous and pervasive computing systems. However, Low PAN technology is still open to being adapted to existing interoperability mechanisms defined for the Internet. Service-Oriented-Architecture (SOA) is one of the key paradigms that enables the deployment of services at large-scale over the Internet domain and its integration with LoWPANs has opened new pathways for novel applications and research. Despite the need to integrate SOA with LoWPANs, only handful efforts are underway to achieve the goal. In this paper, we discuss the integration of LoWPANs with Service-Oriented-Architecture (SOA) for seamless provisioning of services in LoWPANs, especially considering the future of LoWPANs, i.e., IPv6-enabled LoWPANs (6LoWPANs). We first present an overview about the general concepts of SOA and its applicability onto low-power devices. Then, we discuss 6LoWPAN, a milestone protocol that bridged the gap between low-power devices and the IP world and discuss the advantages, challenges and opportunities for porting SOA over LoWPANs. We also present the main research efforts that contributed to featuring the integration LoWPANs with SOA and we draw a research roadmap on potential research directions and challenges for achieving an efficient coupling among LoWPANs and SOA. read more... read less...

Keywords: Wireless Sensor Networks, 6lowpan, Service Oriented Architecture.

Adaptive Scheduling of Message Carrying in a Pigeon Network

JUSPN, volume-01 , Issue 1 (2010), PP 29 - 37

Published: 21 Apr 2011

DOI: 10.5383/JUSPN.01.01.004

by Jiazhen Zhou, Jiang Li, Kenneth Mitchell from Department of Systems and Computer Science Howard University, Washington DC, 20059 Department of Computer Science Electrical Engineering University of Missouri -Kansas City 64110

Abstract: In adverse environments where real-time communications are not always available, a delay to learn network may be the only choice. A special type of delay tolerant network known as a ``pigeon network'' utilizes controllable special purpose vehicles called` `pigeons'' to convey messages among segregated areas. A challenging problem studied in this paper is how to schedule a` `pigeon'' to enter/leave particular segregated area in an optimal way so that the average delay of messages is minimized. This problem falls in the range of server vacation queueing model. Unfortunately, the amount of work in the open literature that address es the optimal scheduling (service discipline) problem is very limited, especially when busty traffic c is considered. Based on an analysis of a scenario with deterministic and Poisson arrivals, we propose an adaptive scheduling scheme that alternates the service disciplines according to the trend of message accumulation on the home/foreign host. This adaptive scheme shows good performance and flexibility in adjusting to the dynamic s of busty and non- busty traffic. read more... read less...

Keywords: Disruption/Delay -tolerant networking, pigeon networks, scheduling, service discipline

New Solutions for Feasible and Coherent Reconfigurations of Multi-Agent Embedded Software Architectures

JUSPN, volume-01 , Issue 1 (2010), PP 19 - 28

Published: 21 Apr 2011

DOI: 10.5383/juspn.01.01.003

by Mohamed Khalgui, Atef Gharbic from Martin Luther University, Germany, Xidian University, China, University of Carthage, Tunisia,

Abstract: The paper deals with reconfigurable multi-agent distributed embedded control systems following the component -based InternationalIndustrialStandardIEC61499inwhichaFunctionBlock(abbreviatedbyFB)isanevent-triggered software component owningdataandacontrolapplicationisadistributednetworkofFunctionBlocks.Tohandleall possible industrial cases, we classifyreconfigurationscenariosintothreeformsbeforewedefineanarchitectureof reconfigurable multi-agent systems where a Reconfiguration Agent modelled by nested state machines is affected to each device of the execution environment to apply local reconfigurations, and a Coordination Agent is proposed for any coordination between devices in order to guarantee safe and adequate distributed reconfigurations .A Communication Protocol is proposed to allow a feasible coordination between agents by using well-defined Coordination Matrices. We model the agents according to the formalism Net Condition/Event Systems (abbrev. NCES) which is a rich extension of Petri nets, and apply the model checker SESA to validate the coordination between agents. Indeed, we should verify that whenever a reconfiguration scenario is applied in a device, the remote devices should react as soon as possible according to user requirements. We developed the tool "Protocol Re cone" for the visual simulation of the inter-agent protocol which is applied in the paper to two benchmark production systems available at Martin Luther University. read more... read less...

Keywords: Function Block, Embedded System, Multi-Agent, Distributed Reconfiguration, Model Checking, Simulation.

Ambient Things on the Web

JUSPN, volume-01 , Issue 1 (2010), PP 1 - 8

Published: 20 Apr 2011

DOI: 10.5383/JUSPN.01.01.001

by Sujith Samuel Mathew, Yacine Atif, Quan Z. Sheng, Zakaria Maamar from School of Computer Science, University of Adelaide, Adelaide, Australia Faculty of IT, UAE University, Al Ain, UAE College of IT, Zayed University, Dubai, UAE

Abstract: Recent advances in Radio Frequency Identification (RFID), wireless sensors and Web services have led to the proliferation of physical things being triggered from the World Wide Web (WWW). The resulting information overflow creates new challenges and at the same time promises a new generation of ubiquitous applications. In this context, managing the large number of things that could be on the Web is exponentially complex. Web application developers require a new architecture for categorizing things so as to facilitate their deployment and management. Failing to do so may result in redundant efforts to put into integrating things in future ubiquitous applications, because of the absence of a common specification of things. In this paper, we propose a classification of things based on their common characteristics and discuss some related properties. Using this classification, an approach is developed to categorize things so that future Web architects can clearly distinguish between different types of things when building context-aware applications on the Web. To illustrate how this classification helps in creating ubiquitous applications, a prototype of an ambient instructional support in a pervasive learning institution is illustrated. read more... read less...

Keywords: Ambient Environments, Web of Things, RFID, Ontology.