Publish/subscribe architecture for mobile ad hoc networks

Publish/Subscribe architectures have been widely studied and applied in wired networks. However, their deployment on mobile ad hoc networks still presents a lot of challenges. This work proposes and analyzes a solution for such networks using the nodes' movement to disseminate publications to the whole network with few transmissions. Our proposal does not build dissemination trees which incur in a high cost to keep them updated due to constant changes in the topology, and does not even require beacons exchanges in order to sustain a neighborhood table. Our experiments show that we are able to achieve better results than a gossip-based algorithm and other solutions found in the literature

Middleware for multi-client and multi-server mobile applications

With popularization of mobile computing, many developers have faced problems due to great heterogeneity of devices. To address this issue, we present in this work a middleware for multi-client and multi-server mobile applications. We assume that the middleware at the server side has no resource restrictions, whereas at the client side it is light and does not incur much overhead to the applications, since the mobile device has several limitations. Offering a transparent communication API and allowing applications to divide their work amongst server and client sides, the proposed middleware becomes a viable alternative for development of distributed and mobile applications. We present as a case study an event notification service and show how it benefits from the proposed middlewar

Understanding and using mobility on Publish/Subscribe based architectures for MANETs

Mobile Ad Hoc Networks present several new challenges, mainly due to mobility. Publish/Subscribe is a communication paradigm that fits this network model well since the entities involved in the communication process do not need to be online at the same time or know each otherpsilas addresses. In order to develop properly a Pub/Sub based Architecture for MANETs, it is essential that designers understand how mobility impacts the performance of any solution. This work presents an analysis of the influence of mobility on a previous solution and extends it based on a different perspective on mobility in MANETs. We show that in using this new approach we have managed to achieve better match rates while sending substantially fewer messages

Publish/subscribe architecture for mobile ad hoc networks

Publish/Subscribe architectures have been widely studied and applied in wired networks. However, their deployment on mobile ad hoc networks still presents a lot of challenges. This work proposes and analyzes a solution for such networks using the nodes' movement to disseminate publications to the whole network with few transmissions. Our proposal does not build dissemination trees which incur in a high cost to keep them updated due to constant changes in the topology, and does not even require beacons exchanges in order to sustain a neighborhood table. Our experiments show that we are able to achieve better results than a gossip-based algorithm and other solutions found in the literature

The impact of mobility on Mobile Ad Hoc Networks through the perspective of complex networks

Mobile Ad Hoc Networks (MANETs) are wireless networks where nodes’ exchange of messages does not rely on any previously deployed infrastructure. Portable devices that are capable of wireless communication have become extremely popular making possible the establishment of wide ubiquitous networks. Users connected to such networks can access the provided services anywhere and anytime. Nevertheless, this architecture suffers from a highly unstable topology since links between nodes break constantly due to users’ movement. Mobility has a paramount influence on the network topology. Therefore, it is of utmost importance to understand the impact of mobility in MANETs. In this work, we perform a thorough analysis on how mobility shape the behavior of MANETs. Our range of observation varies from general MANETs composed of walking users to a next generation of MANETs formed by vehicles moving either in a city environment or in a highway scenario, namely Vehicular Ad Hoc Networks (VANETs). Our analyses are performed observing the networks through the perspective of complex networks. We were able to identify underlying characteristics of these networks and showed how these observations can be used to improve the performance of MANETs

Decentralized intrusion detection in wireless sensor networks

Wireless sensor networks (WSNs) have many potential applications. Furthermore, in many scenarios WSNs are of interest to adversaries and they become susceptible to some types of attacks since they are deployed in open and unprotected environments and are constituted of cheap small devices. Preventive mechanisms can be applied to protect WSNs against some types of attacks. However, there are some attacks for which there is no known prevention methods. For these cases, it is necessary to use some mechanism of intrusion detection. Besides preventingth e intruder from causingda mages to the network, the intrusion detection system (IDS) can acquire information related to the attack techniques, helpingin the development of prevention systems. In this work we propose an IDS that fits the demands and restrictions of WSNs. Simulation results reveal that the proposed IDS is efficient and accurate in detecting different kinds of simulated attacks

Decentralized intrusion detection in wireless sensor networks

Wireless sensor networks (WSNs) have many potential applications. Furthermore, in many scenarios WSNs are of interest to adversaries and they become susceptible to some types of attacks since they are deployed in open and unprotected environments and are constituted of cheap small devices. Preventive mechanisms can be applied to protect WSNs against some types of attacks. However, there are some attacks for which there is no known prevention methods. For these cases, it is necessary to use some mechanism of intrusion detection. Besides preventingth e intruder from causingda mages to the network, the intrusion detection system (IDS) can acquire information related to the attack techniques, helpingin the development of prevention systems. In this work we propose an IDS that fits the demands and restrictions of WSNs. Simulation results reveal that the proposed IDS is efficient and accurate in detecting different kinds of simulated attacks

Adaptive security protocol selection for mobile computing

The mobile computing paradigm has introduced new problems for application developers. Challenges include heterogeneity of hardware, software, and communication protocols, variability of resource limitations and varying wireless channel quality. In this scenario, security becomes a major concern for mobile users and applications. Security requirements for each application are different, as well as the hardware capabilities of each device. To make things worse, wireless medium conditions may change dramatically with time, incurring great impact on performance and QoS guarantees for the application. Currently, most of the security solutions for mobile devices use a static set of algorithms and protocols for services such as cryptography and hashes. In this work we propose a security service, which works as a middleware, with the ability to dynamically change the security protocols used between two peers. These changes can occur based on variations on wireless medium parameters and system resource usage, available hardware resources, application-defined QoS metrics, and desired data "security levels". We compare our solution to some widespread static security protocols, demonstrate how our middleware is able to adapt itself over different conditions of medium and system, and how it can provide a performance gain in the execution of cryptographic primitives, through the use of data semantics. Keywords: Mobile computing; Autonomous computing; Adaptive computing; Security; Data semantics