Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632098
B. Batista, G. Campos, M. Fernandez
The OpenFlow architecture is a proposal from the Clean Slate initiative to define a new Internet architecture where the network devices are simple, and the control and management plane is performed by a centralized controller. The simplicity and centralization architecture makes it reliable and inexpensive. However enterprise network administrators are not familiar with this new concept of network management and there is a shortage of tools that simplify the task of manage a OpenFlow network using a simple interface. The concept of policies is easier to grasp than the concept of OpenFlow flows, because companies use policy to express employee rights and duties in a particular context. This paper proposes a Policy Based OpenFlow Network Management (PBONM) framework to manage the OpenFlow networks using the policies definition language like Ponder to define OpenFlow flows of easy way for the network administrators.
{"title":"A proposal of policy based OpenFlow network management","authors":"B. Batista, G. Campos, M. Fernandez","doi":"10.1109/ICTEL.2013.6632098","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632098","url":null,"abstract":"The OpenFlow architecture is a proposal from the Clean Slate initiative to define a new Internet architecture where the network devices are simple, and the control and management plane is performed by a centralized controller. The simplicity and centralization architecture makes it reliable and inexpensive. However enterprise network administrators are not familiar with this new concept of network management and there is a shortage of tools that simplify the task of manage a OpenFlow network using a simple interface. The concept of policies is easier to grasp than the concept of OpenFlow flows, because companies use policy to express employee rights and duties in a particular context. This paper proposes a Policy Based OpenFlow Network Management (PBONM) framework to manage the OpenFlow networks using the policies definition language like Ponder to define OpenFlow flows of easy way for the network administrators.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131116696","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632138
Hichem Besbes, S. B. Rayana, G. R. Othman
In the case of memoryless MIMO channel and when the channel matrix is ill-conditioned, it is well known that performances of the Maximum Likelihood (ML) equalizer are well pronounced, compared to MMSE and ZF equalizers. In dispersive channels the conventional equalizer intends to cancel the inter-symbol interference, and did not take into the account the conditioning of the channel matrix. It intends to inverse the channel matrix somehow, which may cause noise enhancement and performances degradation. Using this fact and in order to overcome this issue, we propose in this paper a joint partial equalization and ML detection approach, where the equalizer is built based on a novel non-quadratic criterion. The proposed criterion ensures that the equalized channel matrix conserves its conditioning; which will be handled by the ML detector. Simulation results show that the improvement is well pronounced in cases where the channel matrix is ill-conditioned.
{"title":"A non-quadratic criterion for FIR MIMO channel equalization","authors":"Hichem Besbes, S. B. Rayana, G. R. Othman","doi":"10.1109/ICTEL.2013.6632138","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632138","url":null,"abstract":"In the case of memoryless MIMO channel and when the channel matrix is ill-conditioned, it is well known that performances of the Maximum Likelihood (ML) equalizer are well pronounced, compared to MMSE and ZF equalizers. In dispersive channels the conventional equalizer intends to cancel the inter-symbol interference, and did not take into the account the conditioning of the channel matrix. It intends to inverse the channel matrix somehow, which may cause noise enhancement and performances degradation. Using this fact and in order to overcome this issue, we propose in this paper a joint partial equalization and ML detection approach, where the equalizer is built based on a novel non-quadratic criterion. The proposed criterion ensures that the equalized channel matrix conserves its conditioning; which will be handled by the ML detector. Simulation results show that the improvement is well pronounced in cases where the channel matrix is ill-conditioned.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131304406","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632108
Seytkamal Medetov, M. Bakhouya, J. Gaber, M. Wack
The Mobile Ad hoc Networks (MANETs) are communication networks formed on the fly by radio-equipped mobile nodes without relying on any fixed infrastructure. To increase the lifetime of such network, efficient use of energy is a critical issue, because significant energy is consumed by the redundant messages broadcasted on the communication area. To regulate redundant rebroadcasts, which can cause more collisions and requires more energy, recently there have been developed numerous broadcasting techniques. In this paper, we have evaluated and compared an adaptive information dissemination algorithm with other MANETs broadcasting protocols with respect to the energy efficiency.
{"title":"Evaluation of an energy-efficient broadcast protocol in mobile ad hoc networks","authors":"Seytkamal Medetov, M. Bakhouya, J. Gaber, M. Wack","doi":"10.1109/ICTEL.2013.6632108","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632108","url":null,"abstract":"The Mobile Ad hoc Networks (MANETs) are communication networks formed on the fly by radio-equipped mobile nodes without relying on any fixed infrastructure. To increase the lifetime of such network, efficient use of energy is a critical issue, because significant energy is consumed by the redundant messages broadcasted on the communication area. To regulate redundant rebroadcasts, which can cause more collisions and requires more energy, recently there have been developed numerous broadcasting techniques. In this paper, we have evaluated and compared an adaptive information dissemination algorithm with other MANETs broadcasting protocols with respect to the energy efficiency.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126638039","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632123
Tarik Anouari, A. Haqiq
WiMAX (Worldwide Interoperability for Microwave Access) is a wireless communication standard. Today largely used as a mode of transmission and access to broadband Internet. WiMAX is based upon IEEE Standard 802.16, it supports Point-to-MultiPoint (PMP) as well as Mesh mode. In this work, our main objective is to compare through simulations, the QoS performance parameters (Average throughput, average jitter and average delay) of NOAH (NO Ad-Hoc Routing Agent) and DSDV (Destination-Sequenced Distance-Vector routing), under Random Waypoint Mobility Model by varying the nodes speed. Simulator NS-2 was used. The simulation results show that NOAH routing protocol performed better than DSDV protocol in term of average jitter and average delay, however average throughput values of both protocols are almost similar.
WiMAX(全球微波接入互操作性)是一种无线通信标准。今天主要使用宽带作为传输和接入方式的互联网。WiMAX基于IEEE标准802.16，它支持点对多点(PMP)和Mesh模式。在这项工作中，我们的主要目标是通过模拟比较随机路点移动模型下，通过改变节点速度，NOAH (NO Ad-Hoc路由代理)和DSDV(目的地序列距离矢量路由)的QoS性能参数(平均吞吐量，平均抖动和平均延迟)。使用模拟器NS-2。仿真结果表明，NOAH路由协议在平均抖动和平均延迟方面优于DSDV协议，但两种协议的平均吞吐量几乎相同。
{"title":"Performance analysis of routing protocols in WiMAX using Random Waypoint model","authors":"Tarik Anouari, A. Haqiq","doi":"10.1109/ICTEL.2013.6632123","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632123","url":null,"abstract":"WiMAX (Worldwide Interoperability for Microwave Access) is a wireless communication standard. Today largely used as a mode of transmission and access to broadband Internet. WiMAX is based upon IEEE Standard 802.16, it supports Point-to-MultiPoint (PMP) as well as Mesh mode. In this work, our main objective is to compare through simulations, the QoS performance parameters (Average throughput, average jitter and average delay) of NOAH (NO Ad-Hoc Routing Agent) and DSDV (Destination-Sequenced Distance-Vector routing), under Random Waypoint Mobility Model by varying the nodes speed. Simulator NS-2 was used. The simulation results show that NOAH routing protocol performed better than DSDV protocol in term of average jitter and average delay, however average throughput values of both protocols are almost similar.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127815462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632139
Zebing Feng, Z. Feng, Qixun Zhang
Spectrum access is an important research topic in cognitive radio networks, in which secondary users (SUs) manage to utilize the licensed spectrum bands of primary users opportunistically. However, there is a tradeoff between the access opportunities for SUs and communication constraints from primary networks. Moreover, considering the interplay among SUs sharing the limited spatial access resources, how much the access opportunity a SU can derive become complex to determine. In this paper, to protect the primary users(PUs) from the interference caused by SUs, a location-aware discrete region model for spatial spectrum access opportunities of SUs is highlighted, in which the exact value of access opportunity is quantitative as the expected allowed-transmitting number (EATN) of SUs surrounding a PU. Considering the impact of SUs transmission probability and mobility, a probabilistic analysis and a finite-state Markov chain is undertaken. Simulation results show the change rules of SUs access opportunities with parameters of primary and secondary networks, which is full of conductive in determining the deployment and operation of secondary network.
{"title":"A location-aware discrete region approach for spatial access opportunity analysis in cognitive radio networks","authors":"Zebing Feng, Z. Feng, Qixun Zhang","doi":"10.1109/ICTEL.2013.6632139","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632139","url":null,"abstract":"Spectrum access is an important research topic in cognitive radio networks, in which secondary users (SUs) manage to utilize the licensed spectrum bands of primary users opportunistically. However, there is a tradeoff between the access opportunities for SUs and communication constraints from primary networks. Moreover, considering the interplay among SUs sharing the limited spatial access resources, how much the access opportunity a SU can derive become complex to determine. In this paper, to protect the primary users(PUs) from the interference caused by SUs, a location-aware discrete region model for spatial spectrum access opportunities of SUs is highlighted, in which the exact value of access opportunity is quantitative as the expected allowed-transmitting number (EATN) of SUs surrounding a PU. Considering the impact of SUs transmission probability and mobility, a probabilistic analysis and a finite-state Markov chain is undertaken. Simulation results show the change rules of SUs access opportunities with parameters of primary and secondary networks, which is full of conductive in determining the deployment and operation of secondary network.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"91 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117296681","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632111
Ghofrane Fersi, W. Louati, M. B. Jemaa
Ring-based protocols in Wireless Sensor Networks are facing a major challenge on their bootstrapping phase since at the end of this step, all the nodes should be placed into one global consistent ring. Existing bootstrapping ring-based protocols form initially multiple consistent rings and propose solutions to heal these rings into a global consistent one. Our proposed solution avoids the formation of separated rings and forms directly one global consistent ring by orchestrating the nodes joining process and avoiding concurrent joining. Simulation results show that our approach ensures network stabilization in a short time and without consuming a lot of energy.
{"title":"Consistent and efficient bootstrapping ring-based protocol in randomly deployed wireless sensor networks","authors":"Ghofrane Fersi, W. Louati, M. B. Jemaa","doi":"10.1109/ICTEL.2013.6632111","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632111","url":null,"abstract":"Ring-based protocols in Wireless Sensor Networks are facing a major challenge on their bootstrapping phase since at the end of this step, all the nodes should be placed into one global consistent ring. Existing bootstrapping ring-based protocols form initially multiple consistent rings and propose solutions to heal these rings into a global consistent one. Our proposed solution avoids the formation of separated rings and forms directly one global consistent ring by orchestrating the nodes joining process and avoiding concurrent joining. Simulation results show that our approach ensures network stabilization in a short time and without consuming a lot of energy.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130729289","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632116
Yu Chen, I. Darwazeh
An Internet traffic trace over gigabit Ethernet contains information on arrival time and size of every packet over the collection period. An important problem is to model the latency and packet losses within the trace. The Lindley equation is a general form of describing the evolution of queueing delay processes and queue length processes, both of which are tightly associated with the latency and packet losses. We report on our use of the Lindley equation to analyse publicly-available link-layer data from a gigabit Ethernet gateway and discuss the performance of packet queueing delay and queue length based on the data.
{"title":"Quality of service (QoS) analysis of an Internet traffic trace over gigabit Ethernet","authors":"Yu Chen, I. Darwazeh","doi":"10.1109/ICTEL.2013.6632116","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632116","url":null,"abstract":"An Internet traffic trace over gigabit Ethernet contains information on arrival time and size of every packet over the collection period. An important problem is to model the latency and packet losses within the trace. The Lindley equation is a general form of describing the evolution of queueing delay processes and queue length processes, both of which are tightly associated with the latency and packet losses. We report on our use of the Lindley equation to analyse publicly-available link-layer data from a gigabit Ethernet gateway and discuss the performance of packet queueing delay and queue length based on the data.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125757103","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632080
Zhao Li, Jun Gu, Qin Liu
In this paper an interference alignment (IA) based dynamic spectrum sharing and user scheduling scheme for cognitive radio (CR) multi-input multi-output (MIMO) uplink system with multiple secondary users is proposed. The difference of spatial transmission performance originating from various channel matrices is exploited to implement appropriate user scheduling. Then by IA processing, cognitive transmission is confined to subspace orthogonal to the authorized signal subspace. Consequently, opportunistic interference-free sharing of idle spatial subchannel(s) licensed to the primary is achieved. Simulation results show that the proposed strategy could utilize idle spatial channel resource effectively and obtain multiuser diversity gain. On the premise that primary transmission is protected from disturbing, cognitive throughput is significantly improved.
{"title":"Dynamic spectrum sharing and user scheduling for CR-MIMO system based on interference alignment","authors":"Zhao Li, Jun Gu, Qin Liu","doi":"10.1109/ICTEL.2013.6632080","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632080","url":null,"abstract":"In this paper an interference alignment (IA) based dynamic spectrum sharing and user scheduling scheme for cognitive radio (CR) multi-input multi-output (MIMO) uplink system with multiple secondary users is proposed. The difference of spatial transmission performance originating from various channel matrices is exploited to implement appropriate user scheduling. Then by IA processing, cognitive transmission is confined to subspace orthogonal to the authorized signal subspace. Consequently, opportunistic interference-free sharing of idle spatial subchannel(s) licensed to the primary is achieved. Simulation results show that the proposed strategy could utilize idle spatial channel resource effectively and obtain multiuser diversity gain. On the premise that primary transmission is protected from disturbing, cognitive throughput is significantly improved.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115163141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632131
M. Koca, H. Sari
We present a general upper bounding framework for the average bit error probability (ABEP) of generalized spatial modulation (G-SM) over correlated Rayleigh and Rician channels. Our approach is applicable to any multiple-input multiple-output (MIMO) configuration and linear modulation alphabet. The framework also incorporates possibly correlated Gaussian channel estimates. The ABEP with perfect channel state information (CSI) can be derived as a special case. This approach not only provides tight ABEP upper bounds but also serves as a performance optimization tool to choose the best transmit antenna group configuration. All theoretical results are validated by simulation results shown using phase shift keying (PSK) and quadrature amplitude modulation (QAM) constellations.
{"title":"Generalized spatial modulation over correlated fading channels: Performance analysis and optimization","authors":"M. Koca, H. Sari","doi":"10.1109/ICTEL.2013.6632131","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632131","url":null,"abstract":"We present a general upper bounding framework for the average bit error probability (ABEP) of generalized spatial modulation (G-SM) over correlated Rayleigh and Rician channels. Our approach is applicable to any multiple-input multiple-output (MIMO) configuration and linear modulation alphabet. The framework also incorporates possibly correlated Gaussian channel estimates. The ABEP with perfect channel state information (CSI) can be derived as a special case. This approach not only provides tight ABEP upper bounds but also serves as a performance optimization tool to choose the best transmit antenna group configuration. All theoretical results are validated by simulation results shown using phase shift keying (PSK) and quadrature amplitude modulation (QAM) constellations.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127152142","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-05-06DOI: 10.1109/ICTEL.2013.6632113
Mohammed Ridouani, A. Hayar
Cognitive radio is a promising technology that uses radio spectrum opportunistically and efficiently. In this paper, we propose a general scheme for enhancing the cognitive sources of data transmission to provide "Always Transmit" solution using mixed strategies in cognitive radio context. Indeed, we propose to combine underlay and interweave approaches depending on the activity of the primary system. We analyze the Ergodic Capacity of cognitive transmission under joint transmit power constraint and interference power constraint over Nakagami fading channels. We show the gain of our approach versus other approaches in literature. This framework accounts for most of the parameters that affect the performance and provides fundamental insights that may be of value to the transmission scenario, such as the spectrum sensing duration, spectrum hole detection, primary system bandwidth occupancy, transmit and interference power constraints, and fading.
{"title":"General scheme for always transmit solution in cognitive radio systems","authors":"Mohammed Ridouani, A. Hayar","doi":"10.1109/ICTEL.2013.6632113","DOIUrl":"https://doi.org/10.1109/ICTEL.2013.6632113","url":null,"abstract":"Cognitive radio is a promising technology that uses radio spectrum opportunistically and efficiently. In this paper, we propose a general scheme for enhancing the cognitive sources of data transmission to provide \"Always Transmit\" solution using mixed strategies in cognitive radio context. Indeed, we propose to combine underlay and interweave approaches depending on the activity of the primary system. We analyze the Ergodic Capacity of cognitive transmission under joint transmit power constraint and interference power constraint over Nakagami fading channels. We show the gain of our approach versus other approaches in literature. This framework accounts for most of the parameters that affect the performance and provides fundamental insights that may be of value to the transmission scenario, such as the spectrum sensing duration, spectrum hole detection, primary system bandwidth occupancy, transmit and interference power constraints, and fading.","PeriodicalId":430600,"journal":{"name":"ICT 2013","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127699789","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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