Hesselbach, X.; Amazonas, J.; Villanueva, S.; Botero, J. Journal of network and computer applications Vol. 69, p. 14-26 DOI: 10.1016/j.jnca.2016.02.025 Data de publicació: 2016-07-01 Article en revista
The main resource allocation research challenge in network virtualization is the Virtual Network Embedding (VNE) Problem. It consists of two stages, usually performed separately: node mapping and link mapping. A new mathematical multi-constraint routing framework for linear and non-linear metrics called "paths algebra" has already been proposed to solve the second stage, providing good results thanks to its flexibility. Unlike existing approaches, paths algebra is able to include any kind of network parameters (linear and non-linear) to solve VNE in reasonable runtime. While paths algebra had only been used to solve one stage (link mapping) of the VNE, this paper suggests an improvement to solve VNE using the paths algebra-based strategy by coordinating, in a single stage, the mapping of nodes and links based on a ranking made of the bi-directional pair of nodes of the substrate network, ordered by their available resources. Simulation results show that the New Paths Algebra-based strategy shows significant performance improvements when compared against the uncoordinated paths Algebra-based link mapping approach.
The main resource allocation research challenge in network virtualization is the Virtual Network Embedding (VNE) Problem. It consists of two stages, usually performed separately: node mapping and link mapping. A new mathematical multi-constraint routing framework for linear and non-linear metrics called
Named Data Networking (NDN) is a promising network architecture being considered as a possible replacement for the current IP-based Internet infrastructure. However, NDN is subject to congestion when the number of data packets that reach one or various routers in a certain period of time is so high than its queue gets overflowed. To address this problem many congestion control protocols have been proposed in the literature which, however, they are highly sensitive to their control parameters as well as unable to predict congestion traffic well enough in advance. This paper develops an Adaptive Congestion Control Protocol in NON (ACCPndn) by learning capacities in two phases to control congestion traffics before they start impacting the network performance. In the first phase - adaptive training - we propose a Time-Lagged Feedforward Network (TLFN) optimized by hybridization of particle swarm optimization and genetic algorithm to predict the source of congestion together with the amount of congestion. In the second phase -fuzzy avoidance- we employ a non-linear fuzzy logic-based control system to make a proactive decision based on the outcomes of first phase in each router per interface to control and/or prevent packet drop well enough in advance. Extensive simulations and results show that ACCPndn sufficiently satisfies the applied performance metrics and outperforms two previous proposals such as NACK and HoBHIS in terms of the minimal packet drop and high-utilization (retrying alternative paths) in bottleneck links to mitigate congestion traffics.
Ricciardi, S.; Palmieri, F.; Castiglione, A.; Careglio, D. Journal of network and computer applications Vol. 56, p. 41-47 DOI: 10.1016/j.jnca.2015.06.014 Data de publicació: 2015-10-01 Article en revista
Flexgrid Optical Networks provide higher spectrum efficiency and flexibility in comparison to traditional wavelength switched optical networks (WSON) due to the finer granularity in managing communication channels at the WDM layer, thus allowing beyond 100 Gbps transmission capabilities. They also promise allocating part of the traffic aggregation function to the optical layer, thus reducing the use of energy-hungry electronic devices. Accordingly, in this work, we analyzed these architectures from the power consumption perspective by evaluating the energy efficiency derived from introducing the Flexgrid technology in order to allow the shift of grooming and bandwidth aggregation functions at the optical layer, by envisioning a next generation of IP/MPLS-over-flexgrid transport architectures.
In the area of Wireless Sensor Networks (WSNs), improving energy efficiency and network lifetime is one of the most important and challenging issues. Most of the considered WSNs are formed by nodes with limited resources, in which each node plays dual rule of both sensing the environment and relaying traffic to the sink from other nodes. On the one hand, the nodes need to stay alive as long as possible by achieving energy efficiency. On the other hand, they have to provide the required service. This conflict of interest makes game theory very useful in WSNs. Moreover, nodes usually have to make decisions with limited information about the state of the network. Game theory has been used recently in a remarkable amount of research in this area. In this survey, we review the most recent papers about using game theory in WSNs to achieve a trade-off between maximizing the network lifetime and providing the required service. The paper contains a complete taxonomy of games applied to this specific research problem. It summarizes and compares the different published proposals along with tables and statistical charts showing in which domains game theory has been applied recently. Overall, the paper will give to researchers a clear view of the newest trends in this research area, underlining its main challenges and hopefully fostering discussions and new research directions.
Botero, J.; Molina, M.; Hesselbach, X.; De Almeida, J. Journal of network and computer applications Vol. 36, num. 6, p. 1735-1752 DOI: 10.1016/j.jnca.2013.02.029 Data de publicació: 2013-11 Article en revista
One of the main challenges of network virtualization is the virtual network embedding problem (VNE) that consists of mapping virtual network demands in physical network resources. VNE can be decomposed into two stages: virtual node and virtual link mapping. In the first stage, each virtual node is mapped to a suitable node in the physical network whereas the second stage is in charge of mapping the links connecting virtual nodes to paths in the physical network that suit the virtual network demands. In this paper we propose the utilization of a mathematical multi-constraint routing framework called "paths algebra" to solve the virtual link mapping stage. Paths algebra provides the flexibility to introduce an unlimited number of linear and non-linear constraints and metrics to the problem while finding all the eligible paths in the physical network to perform the virtual link mapping resulting in better and more flexible embeddings
One of the main challenges of network virtualization is the virtual network embedding problem (VNE) that consists of mapping virtual network demands in physical network resources. VNE can be decomposed into two stages: virtual node and virtual link mapping. In the first stage, each virtual node is mapped to a suitable node in the physical network whereas the second stage is in charge of mapping the links connecting virtual nodes to paths in the physical network that suit the virtual network demands.
In this paper we propose the utilization of a mathematical multi-constraint routing framework called “paths algebra” to solve the virtual link mapping stage. Paths algebra provides the flexibility to introduce an unlimited number of linear and non-linear constraints and metrics to the problem while finding all the eligible paths in the physical network to perform the virtual link mapping resulting in better and more flexible embeddings.
Hernandez, C.; Muñoz, J.; Esparza, O.; Mata, J.; Hernández-Serrano, J.; Alins, J. Journal of network and computer applications Vol. 36, num. 5, p. 1337-1351 DOI: 10.1016/j.jnca.2012.02.006 Data de publicació: 2013-09 Article en revista
Vehicular Ad Hoc Networks (VANETs) require mechanisms to authenticate messages, identify valid vehicles, and remove misbehaving vehicles. A public key infrastructure (PKI) can be used to provide these functionalities using digital certificates. However, if a vehicle is no longer trusted, its certificates have to be revoked and this status information has to be made available to other vehicles as soon as possible. In this paper, we propose a collaborative certificate status checking mechanism called COACH to efficiently distribute certificate revocation information in VANETs. In COACH, we embed a hash tree in each standard Certificate Revocation List (CRL). This dual structure is called extended-CRL. A node possessing an extended-CRL can respond to certificate status requests without having to send the complete CRL. Instead, the node can send a short response (less than 1 kB) that fits in a single UDP message. Obviously, the substructures included in the short responses are authenticated. This means that any node possessing an extended-CRL can produce short responses that can be authenticated (including Road Side Units or intermediate vehicles). We also propose an extension to the COACH mechanism called EvCOACH that is more efficient than COACH in scenarios with relatively low revocation rates per CRL validity period. To build EvCOACH, we embed an additional hash chain in the extended-CRL. Finally, by conducting a detailed performance evaluation, COACH and EvCOACH are proved to be reliable, efficient, and scalable.
Rivas, D.; Barcelo, J.; Guerrero, M.; Morillo, J. Journal of network and computer applications Vol. 34, num. 6, p. 1942-1955 DOI: 10.1016/j.jnca.2011.07.006 Data de publicació: 2011-11 Article en revista
Mejía, M.; Peña, N.; Muñoz, J.; Esparza, O.; Alzate, M. Journal of network and computer applications Vol. 1, num. 34, p. 39-51 DOI: 10.1016/j.jnca.2010.09.007 Data de publicació: 2011-01-13 Article en revista
Cooperation among nodes is fundamental for the operation of mobile ad hoc networks(MANETs).
In such networks, there could be selfish nodes that use resources from other nodes to send their packets
but that do not offer their resources to forward packets for other nodes.Thus,a cooperation
enforcement mechanism is necessary. Trust models have been proposed as mechanisms to incentive
cooperation in MANET sand some of them are based on game theory concepts. Among game theoretic
trust models, those that make nodes’ strategies evolve genetically have shown promising results for
cooperation improvement. However,current approaches propose a highly centralized genetic evolution
which render them unfeasible for practical purposes in MANETs. In this article, we propose a trust model based on a non-cooperative game that uses a bacterial-like algorithm to let the nodes quickly
learn the appropriate cooperation behavior. Our model is completely distributed, achieves optimal
cooperation values in a small fraction of time compared with centralized algorithms,and adapts
effectively to environmental changes.
Rodriguez-Covili , J.; Ochoa, S. F.; Pino, J. A.; Meseguer, R.; Medina, E.; Royo, M.D. Journal of network and computer applications Vol. 34, num. 6, p. 1883-1893 DOI: 10.1016/j.jnca.2010.12.014 Data de publicació: 2011 Article en revista
Mobile workers doing loosely coupled activities typically perform on demand collaboration in the physical workplace. Communication services available in such work scenarios are uncertain, therefore mobile collaborative applications supporting those activities must provide ad hoc communication mechanisms in order to use each cooperation opportunity. Typically, the complexity of implementing such mobile ad hoc communication mechanisms becomes a challenge that jeopardizes the development of mobile collaborative solutions. This article presents a communication infrastructure named HLMP API dealing with that challenge. HLMP API intends to ease the development of such applications through the reuse of communication services. The infrastructure is an application programming interface that implements the HLMP routing protocol and also some awareness mechanisms that are required for mobile loosely coupled work. Developers using this infrastructure do not have to perform low-level programming.