Ryefone Inc.

Displaying 1-28 of 28 results

  • White Papers // May 2013

    Water-Filling: A Geometric Approach and Its Application to Solve Generalized Radio Resource Allocation Problems

    In this paper, a simple and elegant Geometric WaterFilling (GWF) approach is proposed to solve the unweighted and weighted radio resource allocation problems. Unlike the Conventional Water-Filling (CWF) algorithm, the authors eliminate the step to find the water level through solving a non-linear system from the Karush-Kuhn-Tucker conditions of the...

    Provided By Ryefone Inc.

  • White Papers // Feb 2013

    Throughput Maximization Based on Optimal Access Probabilities in Cognitive Radio System

    Well-established fact shows that the fixed spectrum allocation policy conveys to the low spectrum utilization. The cognitive radio technique promises to improve the low efficiency. This paper proposes an optimized access strategy combining overlay scheme and underlay scheme for the cognitive radio. The authors model the service state of the...

    Provided By Ryefone Inc.

  • White Papers // Feb 2013

    Effective Capacity and Interference Analysis in Multiband Dynamic Spectrum Sensing

    In this paper, the performance of multichannel transmission in cognitive radio is studied. Both QoS constraints and interference limitations are considered. The activities of the Primary Users (PUs) are initially detected by Cognitive Users (CUs) who perform sensing process over multiple channels. They transmit in a single channel at variable...

    Provided By Ryefone Inc.

  • White Papers // Feb 2013

    Integration of 4G Wireless Technologies in a Test-Bed Environment

    Amongst other mandates of the 4th Generation of Wireless Networks (4G), integration and unification of various technologies is a critical subject. In this paper an end-to-end wireless network deployment in a test-bed environment is established to demonstrate a practical model for integration of various wireless technologies used by ISPs to...

    Provided By Ryefone Inc.

  • White Papers // Jan 2013

    Factors Influencing the Adoption of Cloud Computing by Small and Medium-Sized Enterprises (SMEs)

    This paper is to determine the factors influencing the cloud computing adoption by Small and Medium sized Enterprises (SMEs). Based on two dominant theories in the field of diffusion of innovation, a conceptual model is proposed. In order to test the model empirically, an online survey was designed and launched....

    Provided By Ryefone Inc.

  • White Papers // May 2012

    A Fuzzy-Logic-Based Cluster Head Selection Algorithm in VANETs

    Due to vehicles high mobility, there have been many clustering-based MAC protocols proposed to control vehicular ad hoc network topology more effectively. Cluster Head (CH) selection and cluster formation is of paramount importance in a highly dynamic environment such as VANETs. In this paper, the authors propose a novel cluster...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Reliability of Cluster-Based Multichannel MAC Protocols in VANETs

    The IEEE 802.11p or Wireless Access in Vehicular Environment (WAVE) has been adopted as a main technology for Vehicular Ad hoc NETworks (VANETs). Its Medium Access Control (MAC) protocol is based on the Distributed Coordination Function (DCF) of the IEEE 802.11 which has low performance and high collision rate especially...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Competitive Pricing for Spectrum Subleasing for Future Wireless Ad Hoc Networks

    This paper envisions a near future in which the proliferation of wireless ad hoc networks in urban centers causes excessive spectrum pollution on currently allocated unlicensed bands. One solution for this problem is for the operators to lease freshly released spectrum from the regulators and sublease it to agencies in...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Lightweight Mutual RFID Authentication

    A lightweight mutual authentication protocol is proposed for RFID systems in which both the tags and the reader can be authenticated to each other. The proposed protocol is based on the McEliece cryptosystem without requiring Radio Frequency IDentification (RFID) tags to store the large matrices needed in the McEliece cryptosystem....

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Trust-Enhanced Message Security Protocol for Mobile Ad Hoc Networks

    Securing the routing of message in Mobile Ad hoc NETworks (MANETs) is still a challenging issue. This paper proposes an Enhanced Trust-Based Multipath Dynamic Source Routing (DSR) protocol (so-called ETBMDSR) to securely transmit messages in MANETs. The authors' method consists in a combination of soft-encryption, novel trust management strategy, and...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    A New Image Encryption Algorithm Based on a Chaotic DNA Substitution Method

    This paper presents a novel chaos-based algorithm for image encryption. A 2D chaotic map is used to shuffle the image pixel positions. Substitution (confusion) and permutation (diffusion) operations on every block are combined using two perturbed chaotic PWLCM maps in multiple rounds. The authors' proposed algorithm uses a new chaotic...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Novel Power Control Algorithm by Decomposed Geometric Programming Method for CDMA Cognitive Radio Networks

    Traditionally, the frequency spectrum is licensed to users in a rigid manner where the licensee has the exclusive right to access the allocated band. However, an unlicensed (cognitive) user may share a frequency band with a licensed (primary) owner as long as the interference is below a certain threshold. This...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Towards an Efficient Rendezvous Protocol for a Cognitive PAN

    In this paper, the authors describe a rendezvous protocol that enables nodes to quickly and reliably discover an existing channel-hopping cognitive PAN. The proposed protocol does not rely on the presence of a dedicated controller, the availability of a common control channel, or clock synchronization between the cognitive PAN and...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    MAC Performance Modeling of IEEE 802.15.6-Based WBANs Over Rician-Faded Channels

    Since the signal transmission in WBANs takes place around or in the human body, the channel fading significantly affects the error performance of the networks. In this paper, the authors investigate MAC performance of an IEEE 802.15.6-based WBAN operating over a Rician-faded channel. They deploy Bit Error Rate (BER) as...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Relevance-Based Verification of VANET Safety Messages

    Authentication of vehicular safety messages poses a challenge in a high density road-traffic scenario as the verification time for gathered messages gets longer than the average inter-arrival time. This may expose a vehicular network entity to several different security attacks. The existing solutions have addressed the issue either by randomizing...

    Provided By Ryefone Inc.

  • White Papers // Mar 2012

    CSCD: A Simple Channel Scan Protocol to Discover and Join a Cognitive PAN

    The paper describes a simple channel scan protocol through which a station can quickly discover and join an existing piconet following a specified channel-hopping MAC protocol piconet in its vicinity. The proposed MAC protocol is simple and does not need a dedicated control channel. Moreover, the cognitive piconet can operate...

    Provided By Ryefone Inc.

  • White Papers // Jan 2012

    Optimal Resource Allocation for Multimedia Cloud in Priority Service Scheme

    Multimedia cloud is an emerging computing paradigm that can effectively process multimedia applications and provide multi-QoS provisions for customers. Two major challenges exist in multimedia cloud: the resource cost and the service response time. In this paper, the authors employ the proposed queuing model to optimize the resource allocation for...

    Provided By Ryefone Inc.

  • White Papers // Sep 2011

    Scalable Grid Resource Discovery Through Distributed Search

    This paper proposes a simple and scalable web-based model for grid resource discovery for the Internet. The resource discovery model contains the metadata and resource finder web services. The information of resource finder web services is kept in the repositories that are distributed in the application layer of Internet. The...

    Provided By Ryefone Inc.

  • White Papers // Jul 2011

    Optimal Resource Allocation for Video Streaming Over Cognitive Radio Networks

    Cognitive Radio (CR) is a new paradigm in wireless communications to enhance utilization of limited spectrum resources. In this paper, the authors investigate the resource allocation problem for video streaming over spectrum underlay cognitive radio networks where secondary users and primary users transmit data simultaneously in a common frequency band....

    Provided By Ryefone Inc.

  • White Papers // Apr 2011

    Optimal Resource Allocation to Provide QoS Guarantee in Pervasive Health Monitoring Systems

    Pervasive health monitoring is an e-Health service, which plays an important role in prevention and early detection of diseases. In health monitoring systems, a loss or an excessive delay of the critical data may cause a fatal accident. Therefore it is important to provide Quality of Service (QoS) guarantee for...

    Provided By Ryefone Inc.

  • White Papers // Apr 2011

    Optimal Source Rate Allocation in Body Sensor Networks With Energy Harvesting

    Body Sensor Networks (BSNs) are promising in pervasive health monitoring applications. One of the major challenges in BSNs is the sustainable power supply since each body sensor has limited battery capacity. In this paper, the authors optimize the source rate of the sensor to provide an uninterrupted service for BSNs...

    Provided By Ryefone Inc.

  • White Papers // Feb 2010

    Streaming Capacity in Multi-Channel P2P VoD Systems

    Peer-To-Peer (P2P) Video-on-Demand (VoD) systems with multiple channels are called multi-channel P2P VoD systems, which can be categorized into independent-channel P2P VoD systems and correlated-channel P2P VoD systems. Most of the existing P2P VoD systems are independent-channel P2P systems, in which the peers share resources with each other within the...

    Provided By Ryefone Inc.

  • White Papers // Apr 2009

    Prefetching Optimization in P2P VoD Applications

    Most existing Peer-To-Peer (P2P) Video-on-Demand (VoD) systems have been designed and optimized for the sequential playback. In practice, users often want to seek to the positions they are interested in. Such frequent seeks raise a great challenge to the design of the prefetching scheme. In this paper, the authors propose...

    Provided By Ryefone Inc.

  • White Papers // Mar 2009

    Optimal Resource Allocation for Video Communication Over Distributed Systems

    Many multimedia applications involve real-time video communication over distributed systems, in which there is no centralized controller. Examples of such distributed systems are Peer-To-Peer (P2P) networks, wireless ad hoc networks, and wireless sensor networks. In this paper, the authors provide a review of recent advances on optimal resource allocation for...

    Provided By Ryefone Inc.

  • White Papers // Mar 2009

    Improving the Streaming Capacity in P2P VOD Systems With Helpers

    Peer-To-Peer (P2P) Video-on-Demand (VoD) is a promising solution to provide video service to a large number of users. Streaming capacity in a P2P VoD system is defined as the maximal streaming rate that every user can receive. Due to the upload bottleneck, the streaming capacity in the P2P VoD system...

    Provided By Ryefone Inc.

  • White Papers // Feb 2009

    Streaming Capacity in P2P VoD Systems

    Peer-To-Peer (P2P) Video-on-Demand (VoD) has become a popular service on the Internet. However current P2P VoD systems can only provide a video at a low streaming rate. The upper bound of the streaming rate that a P2P VoD system can support becomes an attractive topic. In this paper, the authors...

    Provided By Ryefone Inc.

  • White Papers // Nov 2008

    From Centralized to Decentralized Video Streaming Using Multiple Descriptions Coding

    In this paper, the authors examine the frame loss probabilities for Multiple-Description Coded (MDC) video transmitted over independent paths. They apply an efficient multiple description coding technique for the analysis, and they investigate the impact of drifting error in terms of the probability of receiving freeze frames for reconstructed video....

    Provided By Ryefone Inc.

  • White Papers // Nov 2008

    Video Multicast Over Wireless Ad Hoc Networks Using Distributed Optimization

    Video multicast over wireless ad hoc networks is a quite challenging task. In this paper, the authors propose an optimized video multicast scheme. Firstly, they apply prioritized coding scheme and network coding scheme to eliminate the decoding hierarchy and delivery redundancy. Then, they maximize the aggregate throughput at all the...

    Provided By Ryefone Inc.

  • White Papers // Sep 2011

    Scalable Grid Resource Discovery Through Distributed Search

    This paper proposes a simple and scalable web-based model for grid resource discovery for the Internet. The resource discovery model contains the metadata and resource finder web services. The information of resource finder web services is kept in the repositories that are distributed in the application layer of Internet. The...

    Provided By Ryefone Inc.

  • White Papers // Feb 2013

    Integration of 4G Wireless Technologies in a Test-Bed Environment

    Amongst other mandates of the 4th Generation of Wireless Networks (4G), integration and unification of various technologies is a critical subject. In this paper an end-to-end wireless network deployment in a test-bed environment is established to demonstrate a practical model for integration of various wireless technologies used by ISPs to...

    Provided By Ryefone Inc.

  • White Papers // May 2013

    Water-Filling: A Geometric Approach and Its Application to Solve Generalized Radio Resource Allocation Problems

    In this paper, a simple and elegant Geometric WaterFilling (GWF) approach is proposed to solve the unweighted and weighted radio resource allocation problems. Unlike the Conventional Water-Filling (CWF) algorithm, the authors eliminate the step to find the water level through solving a non-linear system from the Karush-Kuhn-Tucker conditions of the...

    Provided By Ryefone Inc.

  • White Papers // Feb 2013

    Throughput Maximization Based on Optimal Access Probabilities in Cognitive Radio System

    Well-established fact shows that the fixed spectrum allocation policy conveys to the low spectrum utilization. The cognitive radio technique promises to improve the low efficiency. This paper proposes an optimized access strategy combining overlay scheme and underlay scheme for the cognitive radio. The authors model the service state of the...

    Provided By Ryefone Inc.

  • White Papers // Feb 2013

    Effective Capacity and Interference Analysis in Multiband Dynamic Spectrum Sensing

    In this paper, the performance of multichannel transmission in cognitive radio is studied. Both QoS constraints and interference limitations are considered. The activities of the Primary Users (PUs) are initially detected by Cognitive Users (CUs) who perform sensing process over multiple channels. They transmit in a single channel at variable...

    Provided By Ryefone Inc.

  • White Papers // Jan 2012

    Optimal Resource Allocation for Multimedia Cloud in Priority Service Scheme

    Multimedia cloud is an emerging computing paradigm that can effectively process multimedia applications and provide multi-QoS provisions for customers. Two major challenges exist in multimedia cloud: the resource cost and the service response time. In this paper, the authors employ the proposed queuing model to optimize the resource allocation for...

    Provided By Ryefone Inc.

  • White Papers // Jul 2011

    Optimal Resource Allocation for Video Streaming Over Cognitive Radio Networks

    Cognitive Radio (CR) is a new paradigm in wireless communications to enhance utilization of limited spectrum resources. In this paper, the authors investigate the resource allocation problem for video streaming over spectrum underlay cognitive radio networks where secondary users and primary users transmit data simultaneously in a common frequency band....

    Provided By Ryefone Inc.

  • White Papers // Apr 2011

    Optimal Resource Allocation to Provide QoS Guarantee in Pervasive Health Monitoring Systems

    Pervasive health monitoring is an e-Health service, which plays an important role in prevention and early detection of diseases. In health monitoring systems, a loss or an excessive delay of the critical data may cause a fatal accident. Therefore it is important to provide Quality of Service (QoS) guarantee for...

    Provided By Ryefone Inc.

  • White Papers // Apr 2011

    Optimal Source Rate Allocation in Body Sensor Networks With Energy Harvesting

    Body Sensor Networks (BSNs) are promising in pervasive health monitoring applications. One of the major challenges in BSNs is the sustainable power supply since each body sensor has limited battery capacity. In this paper, the authors optimize the source rate of the sensor to provide an uninterrupted service for BSNs...

    Provided By Ryefone Inc.

  • White Papers // Feb 2010

    Streaming Capacity in Multi-Channel P2P VoD Systems

    Peer-To-Peer (P2P) Video-on-Demand (VoD) systems with multiple channels are called multi-channel P2P VoD systems, which can be categorized into independent-channel P2P VoD systems and correlated-channel P2P VoD systems. Most of the existing P2P VoD systems are independent-channel P2P systems, in which the peers share resources with each other within the...

    Provided By Ryefone Inc.

  • White Papers // Apr 2009

    Prefetching Optimization in P2P VoD Applications

    Most existing Peer-To-Peer (P2P) Video-on-Demand (VoD) systems have been designed and optimized for the sequential playback. In practice, users often want to seek to the positions they are interested in. Such frequent seeks raise a great challenge to the design of the prefetching scheme. In this paper, the authors propose...

    Provided By Ryefone Inc.

  • White Papers // Mar 2009

    Optimal Resource Allocation for Video Communication Over Distributed Systems

    Many multimedia applications involve real-time video communication over distributed systems, in which there is no centralized controller. Examples of such distributed systems are Peer-To-Peer (P2P) networks, wireless ad hoc networks, and wireless sensor networks. In this paper, the authors provide a review of recent advances on optimal resource allocation for...

    Provided By Ryefone Inc.

  • White Papers // Mar 2009

    Improving the Streaming Capacity in P2P VOD Systems With Helpers

    Peer-To-Peer (P2P) Video-on-Demand (VoD) is a promising solution to provide video service to a large number of users. Streaming capacity in a P2P VoD system is defined as the maximal streaming rate that every user can receive. Due to the upload bottleneck, the streaming capacity in the P2P VoD system...

    Provided By Ryefone Inc.

  • White Papers // Feb 2009

    Streaming Capacity in P2P VoD Systems

    Peer-To-Peer (P2P) Video-on-Demand (VoD) has become a popular service on the Internet. However current P2P VoD systems can only provide a video at a low streaming rate. The upper bound of the streaming rate that a P2P VoD system can support becomes an attractive topic. In this paper, the authors...

    Provided By Ryefone Inc.

  • White Papers // Nov 2008

    From Centralized to Decentralized Video Streaming Using Multiple Descriptions Coding

    In this paper, the authors examine the frame loss probabilities for Multiple-Description Coded (MDC) video transmitted over independent paths. They apply an efficient multiple description coding technique for the analysis, and they investigate the impact of drifting error in terms of the probability of receiving freeze frames for reconstructed video....

    Provided By Ryefone Inc.

  • White Papers // Nov 2008

    Video Multicast Over Wireless Ad Hoc Networks Using Distributed Optimization

    Video multicast over wireless ad hoc networks is a quite challenging task. In this paper, the authors propose an optimized video multicast scheme. Firstly, they apply prioritized coding scheme and network coding scheme to eliminate the decoding hierarchy and delivery redundancy. Then, they maximize the aggregate throughput at all the...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    A Fuzzy-Logic-Based Cluster Head Selection Algorithm in VANETs

    Due to vehicles high mobility, there have been many clustering-based MAC protocols proposed to control vehicular ad hoc network topology more effectively. Cluster Head (CH) selection and cluster formation is of paramount importance in a highly dynamic environment such as VANETs. In this paper, the authors propose a novel cluster...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Reliability of Cluster-Based Multichannel MAC Protocols in VANETs

    The IEEE 802.11p or Wireless Access in Vehicular Environment (WAVE) has been adopted as a main technology for Vehicular Ad hoc NETworks (VANETs). Its Medium Access Control (MAC) protocol is based on the Distributed Coordination Function (DCF) of the IEEE 802.11 which has low performance and high collision rate especially...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Competitive Pricing for Spectrum Subleasing for Future Wireless Ad Hoc Networks

    This paper envisions a near future in which the proliferation of wireless ad hoc networks in urban centers causes excessive spectrum pollution on currently allocated unlicensed bands. One solution for this problem is for the operators to lease freshly released spectrum from the regulators and sublease it to agencies in...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Lightweight Mutual RFID Authentication

    A lightweight mutual authentication protocol is proposed for RFID systems in which both the tags and the reader can be authenticated to each other. The proposed protocol is based on the McEliece cryptosystem without requiring Radio Frequency IDentification (RFID) tags to store the large matrices needed in the McEliece cryptosystem....

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Trust-Enhanced Message Security Protocol for Mobile Ad Hoc Networks

    Securing the routing of message in Mobile Ad hoc NETworks (MANETs) is still a challenging issue. This paper proposes an Enhanced Trust-Based Multipath Dynamic Source Routing (DSR) protocol (so-called ETBMDSR) to securely transmit messages in MANETs. The authors' method consists in a combination of soft-encryption, novel trust management strategy, and...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    A New Image Encryption Algorithm Based on a Chaotic DNA Substitution Method

    This paper presents a novel chaos-based algorithm for image encryption. A 2D chaotic map is used to shuffle the image pixel positions. Substitution (confusion) and permutation (diffusion) operations on every block are combined using two perturbed chaotic PWLCM maps in multiple rounds. The authors' proposed algorithm uses a new chaotic...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Novel Power Control Algorithm by Decomposed Geometric Programming Method for CDMA Cognitive Radio Networks

    Traditionally, the frequency spectrum is licensed to users in a rigid manner where the licensee has the exclusive right to access the allocated band. However, an unlicensed (cognitive) user may share a frequency band with a licensed (primary) owner as long as the interference is below a certain threshold. This...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Towards an Efficient Rendezvous Protocol for a Cognitive PAN

    In this paper, the authors describe a rendezvous protocol that enables nodes to quickly and reliably discover an existing channel-hopping cognitive PAN. The proposed protocol does not rely on the presence of a dedicated controller, the availability of a common control channel, or clock synchronization between the cognitive PAN and...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    MAC Performance Modeling of IEEE 802.15.6-Based WBANs Over Rician-Faded Channels

    Since the signal transmission in WBANs takes place around or in the human body, the channel fading significantly affects the error performance of the networks. In this paper, the authors investigate MAC performance of an IEEE 802.15.6-based WBAN operating over a Rician-faded channel. They deploy Bit Error Rate (BER) as...

    Provided By Ryefone Inc.

  • White Papers // May 2012

    Relevance-Based Verification of VANET Safety Messages

    Authentication of vehicular safety messages poses a challenge in a high density road-traffic scenario as the verification time for gathered messages gets longer than the average inter-arrival time. This may expose a vehicular network entity to several different security attacks. The existing solutions have addressed the issue either by randomizing...

    Provided By Ryefone Inc.

  • White Papers // Mar 2012

    CSCD: A Simple Channel Scan Protocol to Discover and Join a Cognitive PAN

    The paper describes a simple channel scan protocol through which a station can quickly discover and join an existing piconet following a specified channel-hopping MAC protocol piconet in its vicinity. The proposed MAC protocol is simple and does not need a dedicated control channel. Moreover, the cognitive piconet can operate...

    Provided By Ryefone Inc.

  • White Papers // Jan 2013

    Factors Influencing the Adoption of Cloud Computing by Small and Medium-Sized Enterprises (SMEs)

    This paper is to determine the factors influencing the cloud computing adoption by Small and Medium sized Enterprises (SMEs). Based on two dominant theories in the field of diffusion of innovation, a conceptual model is proposed. In order to test the model empirically, an online survey was designed and launched....

    Provided By Ryefone Inc.