Computing infrastructure issues in distributed communications systems : a survey of operating system transport system architectures

The performance of distributed applications (such as file transfer, remote login, tele-conferencing, full-motion video, and scientific visualization) is influenced by several factors that interact in complex ways. In particular, application performance is significantly affected both by communication infrastructure factors and computing infrastructure factors. Several communication infrastructure factors include channel speed, bit-error rate, and congestion at intermediate switching nodes. Computing infrastructure factors include (among other things) both protocol processing activities (such as connection management, flow control, error detection, and retransmission) and general operating system factors (such as memory latency, CPU speed, interrupt and context switching overhead, process architecture, and message buffering). Due to a several orders of magnitude increase in network channel speed and an increase in application diversity, performance bottlenecks are shifting from the network factors to the transport system factors.This paper defines an abstraction called an "Operating System Transport System Architecture" (OSTSA) that is used to classify the major components and services in the computing infrastructure. End-to-end network protocols such as TCP, TP4, VMTP, XTP, and Delta-t typically run on general-purpose computers, where they utilize various operating system resources such as processors, virtual memory, and network controllers. The OSTSA provides services that integrate these resources to support distributed applications running on local and wide area networks.A taxonomy is presented to evaluate OSTSAs in terms of their support for protocol processing activities. We use this taxonomy to compare and contrast five general-purpose commercial and experimental operating systems including System V UNIX, BSD UNIX, the x-kernel, Choices, and Xinu

Mobile Online Gaming via Resource Sharing

Mobile gaming presents a number of main issues which remain open. These are concerned mainly with connectivity, computational capacities, memory and battery constraints. In this paper, we discuss the design of a fully distributed approach for the support of mobile Multiplayer Online Games (MOGs). In mobile environments, several features might be exploited to enable resource sharing among multiple devices / game consoles owned by different mobile users. We show the advantages of trading computing / networking facilities among mobile players. This operation mode opens a wide number of interesting sharing scenarios, thus promoting the deployment of novel mobile online games. In particular, once mobile nodes make their resource available for the community, it becomes possible to distribute the software modules that compose the game engine. This allows to distribute the workload for the game advancement management. We claim that resource sharing is in unison with the idea of ludic activity that is behind MOGs. Hence, such schemes can be profitably employed in these contexts.Comment: Proceedings of 3nd ICST/CREATE-NET Workshop on DIstributed SImulation and Online gaming (DISIO 2012). In conjunction with SIMUTools 2012. Desenzano, Italy, March 2012. ISBN: 978-1-936968-47-

A gentle transition from Java programming to Web Services using XML-RPC

Exposing students to leading edge vocational areas of relevance such as Web Services can be difficult. We show a lightweight approach by embedding a key component of Web Services within a Level 3 BSc module in Distributed Computing. We present a ready to use collection of lecture slides and student activities based on XML-RPC. In addition we show that this material addresses the central topics in the context of web services as identified by Draganova (2003)

A Middleware for the Internet of Things

The Internet of Things (IoT) connects everyday objects including a vast array of sensors, actuators, and smart devices, referred to as things to the Internet, in an intelligent and pervasive fashion. This connectivity gives rise to the possibility of using the tracking capabilities of things to impinge on the location privacy of users. Most of the existing management and location privacy protection solutions do not consider the low-cost and low-power requirements of things, or, they do not account for the heterogeneity, scalability, or autonomy of communications supported in the IoT. Moreover, these traditional solutions do not consider the case where a user wishes to control the granularity of the disclosed information based on the context of their use (e.g. based on the time or the current location of the user). To fill this gap, a middleware, referred to as the Internet of Things Management Platform (IoT-MP) is proposed in this paper.Comment: 20 pages, International Journal of Computer Networks & Communications (IJCNC) Vol.8, No.2, March 201

Old Wine in New Skins? Revisiting the Software Architecture for IP Network Stacks on Constrained IoT Devices

In this paper, we argue that existing concepts for the design and implementation of network stacks for constrained devices do not comply with the requirements of current and upcoming Internet of Things (IoT) use cases. The IoT requires not only a lightweight but also a modular network stack, based on standards. We discuss functional and non-functional requirements for the software architecture of the network stack on constrained IoT devices. Then, revisiting concepts from the early Internet as well as current implementations, we propose a future-proof alternative to existing IoT network stack architectures, and provide an initial evaluation of this proposal based on its implementation running on top of state-of-the-art IoT operating system and hardware.Comment: 6 pages, 2 figures and table

JXTA-Overlay: a P2P platform for distributed, collaborative, and ubiquitous computing

With the fast growth of the Internet infrastructure and the use of large-scale complex applications in industries, transport, logistics, government, health, and businesses, there is an increasing need to design and deploy multifeatured networking applications. Important features of such applications include the capability to be self-organized, be decentralized, integrate different types of resources (personal computers, laptops, and mobile and sensor devices), and provide global, transparent, and secure access to resources. Moreover, such applications should support not only traditional forms of reliable distributing computing and optimization of resources but also various forms of collaborative activities, such as business, online learning, and social networks in an intelligent and secure environment. In this paper, we present the Juxtapose (JXTA)-Overlay, which is a JXTA-based peer-to-peer (P2P) platform designed with the aim to leverage capabilities of Java, JXTA, and P2P technologies to support distributed and collaborative systems. The platform can be used not only for efficient and reliable distributed computing but also for collaborative activities and ubiquitous computing by integrating in the platform end devices. The design of a user interface as well as security issues are also tackled. We evaluate the proposed system by experimental study and show its usefulness for massive processing computations and e-learning applications.Peer ReviewedPostprint (author's final draft

Improving the detection of the transport mode in the MobilitApp Android application

Millorar els algorismes de detecció del medi de transport dels ciutadans de l'Àrea Metropolitana de Barcelona.El objetivo ha sido el de mejorar la aplicación MobilitApp ya existente, para ello se han añadido dos módulos. El primer módulo que se ha añadido ha sido un detector de accidentes. Debido a que en los anteriores trabajos se estaba tratando con el acelerómetro, nos pareció interesante intentar sacar más provecho al acelerómetro e incluir la funcionalidad de poder detectar cuando el móvil ha sufrido un impacto. Una vez el impacto ha sido detectado se envía un mensaje de emergencia. El segundo módulo consiste en un podómetro, MobilitApp cuenta los pasos del usuario y se presenta junto a una aproximación de la distancia recorrida y del número de calorías quemadas. Como último paso, hemos realizado un análisis sobre las gráficas que se han obtenido de los usuarios tomadas del acelerómetro sobre metro o tren, y hemos comprobado su parecido con una señal sinusoidal. Esta característica ayudará en futuros trabajos para identificar mejor el tipo de sistema de transporte utilizado por el usuario. Además, sería de gran ayuda para ahorrar batería ya que la señal GPS sería menos utilizada.This study aims to improve an existing application for citizen mobility analytics: MobilitApp. Two modules were added to the app in order to develop the desired functionalities. The first module has been added is an accident detector. Because of the previous work involves dealing with the accelerometer, it seemed interesting to try to get more out of the accelerometer and include the functionality to detect when the phone has suffered an impact. Once the impact has been detected, an emergency message is sent. The second module consists of a pedometer, MobilitApp counts the number of the user’s steps and presents them with an approximation of the distance walked and the number of calories burned. As a last step, we have made an analysis of the graphs that have been obtained from the user’s accelerometers travelling on train or subway, and we have checked their resemblance to a sinusoidal signal. This feature will help in future works to better identify the type of public transportation system being used by the user. Besides, it would help to save battery since the GPS signal will be less used.L’objectiu ha estat el de millorar l’aplicació MobilitApp ja existent, per això s’han afegit dos mòduls. El primer mòdul que s’ha afegit ha estat un detector d’accidents. A causa que en els anteriors treballs s’estava tractant amb l’acceleròmetre, ens va semblar interessant intentar treure més profit a l’acceleròmetre e incloure la funcionalitat de poder detectar quan el mòbil ha patit un impacte. Un cop l’impacte ha estat detectat s’envia un missatge d’emergència. El segon mòdul consisteix en un podòmetre, MobilitApp compte els passos de l’usuari i se’ls presenta amb una aproximació de la distància recorreguda y de les calories cremades. Com a últim pas, em fet un anàlisi sobre les gràfiques que s’han obtingut dels usuaris preses de l’acceleròmetre sobre metro o tren, i hem comprovat la seva semblança amb una senyal sinusoïdal. Aquesta característica ens ajudarà en treballs futurs per identificar millor el tipus de sistema de transport utilitzat per l’usuari. A més, seria de gran ajuda per estalviar bateria ja que el senyal GPS seria menys utilitzat