Survey on Broadcast Algorithms for Mobile Ad Hoc Networks

in ACM Computing Surveys (2015), 48(1),

Networking at any time and any place paves the way for a large number of possible applications in ad hoc networks, from disaster relief in remote areas to network extension. Thus, for the past decades ... [more ▼]

Networking at any time and any place paves the way for a large number of possible applications in ad hoc networks, from disaster relief in remote areas to network extension. Thus, for the past decades, many works have been proposed trying to make ad hoc networks a reality. The importance of broadcasting in networking and the broadcast nature of the wireless medium have encouraged researchers to join their efforts on designing efficient dissemination algorithms for Mobile Ad Hoc Networks (MANETs). The many different challenges that MANETs face, such as limited network resources, network partitions, or energy restrictions, gave rise to many different approaches to overcome one or more of those problems. Therefore, literature reveals a huge variety of techniques that have been proposed for efficient message dissemination. In this article, we make an in-depth review of the existing state-of-the-art techniques, as well as propose a new taxonomy that provides a global overview of the most relevant existing algorithms. [less ▲]

Optimizing AEDB Broadcasting Protocol with Parallel Multi-objective Cooperative Coevolutionary NSGAII

in Optimizing AEDB Broadcasting Protocol with Parallel Multi-objective Cooperative Coevolutionary NSGAII (2014)

Efficient Communication Protocols for ad hoc Networks

Doctoral thesis (2013)

Mobile ad hoc networks, also called MANETs, are self-organised networks spontaneously created between neighbouring devices that do not need any infrastructure. The possibility of deploying a communication ... [more ▼]

Mobile ad hoc networks, also called MANETs, are self-organised networks spontaneously created between neighbouring devices that do not need any infrastructure. The possibility of deploying a communication network at any moment and at any place opens a wide range of potential scenarios where the use of an ad hoc network is extremely important and useful. For example, we can imagine an area with no infrastructure, due to a natural disaster (flooding, earthquake, etc.), a war damage or simply a remote location. In such situations, the deployment of an ad hoc network for rescuing or evacuating people is key. %Allowing the communication between groups located in distant areas may be very helpful in critical situations in order to coordinate and reorganise them. However, ad hoc networks are not restricted to safety of disaster situations, they can also be used for gathering sensed data and send it to a remote server, exchanging safety road messages between vehicles or simply for infotainment, etc. Efficient communication protocols are very important for providing good services, but in ad hoc networks is very challenging. It is necessary to deal with packet loss, collisions, mobility, network partitions, fading, energy constraints, obstacles, etc. Due to the intrinsic broadcast nature of wireless medium, dissemination algorithms are one of the most appropriate protocols for communicating devices. Additionally, broadcasting is one of the main low level operation as many applications and even other protocols rely on its service. Therefore, in this thesis, we are proposing two different broadcasting algorithms for efficiently disseminate messages in the network. The first approach relays on an underlying tree topology, while the second is an energy aware algorithm that tries to reduce the energy consumption. In these unpredictable and changeable networks, protocols need to adapt to the current circumstances and this adaptability is usually obtained using thresholds. The values of these thresholds directly influence the behaviour of the algorithm. Finding them is a complex and critical task as protocols are usually very sensitive. We tackle this problem using approximation algorithms or metaheuristics, more specifically, we use a parallel iterative local search and two evolutionary algorithms. In order to ease this process, we have created a modular experimental framework for evaluating, validating and optimising any algorithm in MANETs. [less ▲]

On the Improvement of the Enhanced Distance Based Broadcasting Algorithm

in International Journal of Communication Networks and Distributed Systems (2012), 9(3/4), 225-246

Information Dissemination in VANETs based upon a Tree Topology

in Ad Hoc Networks (2012), 10(1), 111-127

Guidelines for the use and interpretation of assays for monitoring autophagy.

in Autophagy (2012), 8(4), 445-544

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field ... [more ▼]

In 2008 we published the first set of guidelines for standardizing research in autophagy. Since then, research on this topic has continued to accelerate, and many new scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Accordingly, it is important to update these guidelines for monitoring autophagy in different organisms. Various reviews have described the range of assays that have been used for this purpose. Nevertheless, there continues to be confusion regarding acceptable methods to measure autophagy, especially in multicellular eukaryotes. A key point that needs to be emphasized is that there is a difference between measurements that monitor the numbers or volume of autophagic elements (e.g., autophagosomes or autolysosomes) at any stage of the autophagic process vs. those that measure flux through the autophagy pathway (i.e., the complete process); thus, a block in macroautophagy that results in autophagosome accumulation needs to be differentiated from stimuli that result in increased autophagic activity, defined as increased autophagy induction coupled with increased delivery to, and degradation within, lysosomes (in most higher eukaryotes and some protists such as Dictyostelium) or the vacuole (in plants and fungi). In other words, it is especially important that investigators new to the field understand that the appearance of more autophagosomes does not necessarily equate with more autophagy. In fact, in many cases, autophagosomes accumulate because of a block in trafficking to lysosomes without a concomitant change in autophagosome biogenesis, whereas an increase in autolysosomes may reflect a reduction in degradative activity. Here, we present a set of guidelines for the selection and interpretation of methods for use by investigators who aim to examine macroautophagy and related processes, as well as for reviewers who need to provide realistic and reasonable critiques of papers that are focused on these processes. These guidelines are not meant to be a formulaic set of rules, because the appropriate assays depend in part on the question being asked and the system being used. In addition, we emphasize that no individual assay is guaranteed to be the most appropriate one in every situation, and we strongly recommend the use of multiple assays to monitor autophagy. In these guidelines, we consider these various methods of assessing autophagy and what information can, or cannot, be obtained from them. Finally, by discussing the merits and limits of particular autophagy assays, we hope to encourage technical innovation in the field. [less ▲]

Distributed Energy Self-Adaptation in ad hoc Networks

in IEEE Globecom (2010)

Towards Connectivity Improvement in VANETs using Bypass Links

in Abstract book of 2009 IEEE Congress on Evolutionary Computation (2009)

Token Traversal Strategies of a Distributed Spanning Forest Algorithm in Mobile Ad hoc - Delay Tolerant Networks

in IAIT (2009)

This paper presents three distributed and decentralized strategies used for token traversal in spanning forest over Mobile Ad Hoc Delay Tolerant Networks. Such networks are characterized by behaviors like ... [more ▼]

This paper presents three distributed and decentralized strategies used for token traversal in spanning forest over Mobile Ad Hoc Delay Tolerant Networks. Such networks are characterized by behaviors like disappearance of mobile devices, connection disruptions, network partitioning, etc. Techniques based on tree topologies are well known for increasing the efficiency of network protocols and/or applications, such as Dynamicity Aware - Graph Relabeling System (DA-GRS). One of the main features of these tree based topologies is the existence of a token traversing in every tree. The use of tokens enables the creation and maintenance of spanning trees in dynamic environments. Subsequently, managing tree-based backbones relies heavily on the token behavior. An efficient and optimal token traversal can highly impact the design of the tree and its usage. In this article, we present a comparison of three distributed and decentralized techniques available for token management, which are Randomness, TABU and Depth First Search. [less ▲]

BODYF - A Parameterless Broadcasting Protocol over Dynamic Forests

in special session on Parallel and Grid Computing for Optimization as part of The 2008 International Conference High Performance Computing & Simulation (HPCS'08) and in conjunction with The 22nd European Conference on Modeling and Simulation (ECMS 2008) (2008)