Using publish/subscribe for message routing in mobile environments

Publish/subscribe is a mature communication paradigm to route and deliver events from publishers to interested subscribers. Initially conceived for large scale systems, e.g., the Internet, it has been used more recently in new scenarios, e.g., wireless sensor networks and the Internet of Things (IoT), where mobility and dynamicity are the norm. The loose-coupling and asynchronicity of publish/subscribe makes it an interesting choice for IoT scenarios, i.e., each node in an IoT network can choose a different role depending on its location, capabilities, etc. This paper presents MFT-PubSub, a fully mobile and fault tolerant content-based publish/subscribe protocol. Our proposal is a purely reactive solution for mobility in a publish/subscribe system without any kind of limits on the mobility patterns of the nodes. A wireless ad hoc network is created without the need of any previous connections or knowledge on the nodes. Handling the mobility, be it physical or logical, of both clients and brokers. We prove the validity of our solution by experimentation, and compare it with AODV, a routing protocol for mobile ad hoc networking. The simulations show an improvement on message delivery rate over previously used protocols.Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. Research supported by grant TIN2016-79897-P funded by MCIN/AEI/10.13039/501100011033 and by the European Union, and by the Department of Education, Universities and Research of the Basque Government, grant IT-1437-22 (ADIAN)

The last hop of global notification delivery to mobile users. Matching preferences, context, and device constraints.

Events injected by publishers into a publish/subscribe system may reach users through a variety of devices: a stationary desktop, a laptop, a mobile phone, etc. We argue that the "last hop" -- from the network to the output device -- has unique properties, owing to the mobile nature of these devices, and as such demands special consideration. In particular, user's preferences and location may limit what should be forwarded to a device. Furthermore, technological constraints, such as network bandwidth availability and battery power, suggest that the decision when to forward messages is also important for optimizing user's experience. We describe a new publish/subscribe system with volume-limiting mechanisms and explain how user preferences, context, and device constraints can be accommodated in such a system. Notably, based on results of simulations, we propose a simple algorithm for low-cost "prefetching" of notifications to mobile devices in cases when network bandwidth is insufficient

Implementing an event-driven service-oriented architecture in TIP

Many mobile devices have a density of services, many of which are context or location-aware. To function, many of these services have to collaborate with other services, which may be located in many different places and networks. There is often more then on service suitable for the task at hand. To decide which service to use, quality of service measurements like the accuracy or reliability of a service need to be known. Users do not want third parties to have statistics on how and where they used services. Therefore the collaboration needs to be anonymous. This project implements a model of event-based context-aware service collaboration on a publish/subscribe basis. We compare different implementation designs, with focus on anonymity and quality of service of the services

SKYPE: Top-k spatial-keyword publish/subscribe over sliding window

© 2016 VLDB Endowment 21508097/16/03. As the prevalence of social media and GPS-enabled devices, a massive amount of geo-textual data has been generated in a stream fashion, leading to a variety of applications such as location-based recommendation and information dissemination. In this paper, we investigate a novel real-time top-k monitoring problem over sliding window of streaming data; that is, we continuously maintain the top-k most relevant geo-textual messages (e.g., geo-tagged tweets) for a large number of spatial-keyword subscriptions (e.g., registered users interested in local events) simultaneously. To provide the most recent information under controllable memory cost, sliding window model is employed on the streaming geo-textual data. To the best of our knowledge, this is the first work to study top-k spatial-keyword publish/ subscribe over sliding window. A novel system, called Skype (Top-k Spatial-keyword Publish/Subscribe), is proposed in this paper. In Skype, to continuously maintain top-k results for massive subscriptions, we devise a novel indexing structure upon subscriptions such that each incoming message can be immediately delivered on its arrival. Moreover, to reduce the expensive top-k re-evaluation cost triggered by message expiration, we develop a novel cost-based k-skyband technique to reduce the number of re-evaluations in a costeffective way. Extensive experiments verify the great effciency and effectiveness of our proposed techniques

PENERAPAN PROTOKOL PUBLISH / SUBSCRIBE MESSAGING SYSTEM PADA SISTEM WIRELESS BUILDING NETWORK BERBASIS NRF24L01

Wireless sensor network is a common method used in the design of shared resource interconnection infrastructure at a location point to provide optimal performance. The main factor in the design of a wireless sensor network (WSN) communication protocol in the form of coordination optimization efforts between nodes, one of the effective methods that can be made to achieve such conditions is the provision of nodes using the publish / subscribe messaging system protocol. This research discusses the implementation of publish / subscribe messaging system protocol on wireless building network system based on NRF2L01. Discussions include simulation, design, implementation, application testing and system performance both on a work-to-work and performance-by-node performance. The results showed the system was able to monitor all information and control equipment from a building through a web interface making it easier for officers to maintain and supervise a building, then to test the performance of nodes with a fixed data packet size of 32 bytes, the delay value for each node is less than 1 second, then for the minimum throughput 250 kbps data rate obtained at 5.9 Kbps and the maximum throughput obtained at 72 Kbps and for packet loss of at least 0.59% while the maximum packet loss of 13.23% and the standard deviation value of delay, throughput and packet loss are smaller than the average value, the data is not very varied (stable)

Smartphone sensing platform for emergency management

The increasingly sophisticated sensors supported by modern smartphones open up novel research opportunities, such as mobile phone sensing. One of the most challenging of these research areas is context-aware and activity recognition. The SmartRescue project takes advantage of smartphone sensing, processing and communication capabilities to monitor hazards and track people in a disaster. The goal is to help crisis managers and members of the public in early hazard detection, prediction, and in devising risk-minimizing evacuation plans when disaster strikes. In this paper we suggest a novel smartphone-based communication framework. It uses specific machine learning techniques that intelligently process sensor readings into useful information for the crisis responders. Core to the framework is a content-based publish-subscribe mechanism that allows flexible sharing of sensor data and computation results. We also evaluate a preliminary implementation of the platform, involving a smartphone app that reads and shares mobile phone sensor data for activity recognition.Comment: 11th International Conference on Information Systems for Crisis Response and Management ISCRAM2014 (2014

An active, ontology-driven network service for Internet collaboration

Web portals have emerged as an important means of collaboration on the WWW, and the integration of ontologies promises to make them more accurate in how they serve users’ collaboration and information location requirements. However, web portals are essentially a centralised architecture resulting in difficulties supporting seamless roaming between portals and collaboration between groups supported on different portals. This paper proposes an alternative approach to collaboration over the web using ontologies that is de-centralised and exploits content-based networking. We argue that this approach promises a user-centric, timely, secure and location-independent mechanism, which is potentially more scaleable and universal than existing centralised portals

EventMe: Location-Based Event Content Distribution through Human Centric Device-to-Device Communications

Location-based information dissemination has become increasingly popular in the recent years. Extensive research work has been done on the matching of interested parties to event information via publish/subscribe systems. However, the rich content types of such location-specific data, especially when the data are presented in multimedia form, requires efficient methods with low cost to transfer the content to the subscribers. In this paper, the potential of utilising human centric device-to-device (D2D) communications to disseminate location-based event content is investigated. The human centric D2D data dissemination process is formulated as a task assignment problem, which can be modelled as a Integer Quadratically Constrained Quadratic Programming (IQCQP) problem. Since the IQCQP problem is in general NP-hard, a sub- optimal polynomial framework named EventMe is proposed, which is able to compute a solution with guaranteed lower bounds on data distribution capacity in terms of throughput. Through extensive evaluation using several real world datasets, it has shown that EventMe is able to improve the network throughput by 100%-500% compared to baseline methods. A prototype is developed and shows that it is practical to implement EventMe on mobile devices by generating minimal control data overhead