NEC Laboratories

Displaying 1-24 of 24 results

  • White Papers // Feb 2014

    A Case for a Flexible Scalar Unit in SIMT Architecture

    The wide availability and the Single-Instruction Multiple-Thread (SIMT)-style programming model have made Graphics Processing Units (GPUs) a promising choice for high performance computing. However, because of the SIMT style processing, an instruction will be executed in every thread even if the operands are identical for all the threads. To overcome...

    Provided By NEC Laboratories

  • White Papers // Jul 2013

    Building a Delay-Tolerant Cloud for Mobile Data

    Mobile data usage is on a tremendous rise, due not only to increasing number of users but also to an increase in the number of applications that transfer data over the network. Moreover, applications for sharing, sensing, and collaboration have become more popular, causing significant amounts of data to be...

    Provided By NEC Laboratories

  • White Papers // May 2013

    Transparent and Flexible Network Management for Big Data Processing in the Cloud

    The authors introduce FlowComb, a network management framework that helps big data processing applications, such as Hadoop, achieve high utilization and low data processing times. FlowComb predicts application network transfers, sometimes before they start, by using software agents installed on application servers and while remaining completely transparent to the application....

    Provided By NEC Laboratories

  • White Papers // May 2013

    Mobile Data Sync in a Blink

    Mobile applications are becoming increasingly datacentric - often relying on cloud services to store, share, and analyze data. App developers have to frequently manage the local storage on the device (e.g., SQLite databases and file systems), as well as data synchronization with cloud services. Developers have to address common issues...

    Provided By NEC Laboratories

  • White Papers // May 2013

    Modeling and Analytics for Cyber-Physical Systems in the Age of Big Data

    In this paper, the authors argue that the availability of \"Big\" monitoring data on Cyber-Physical Systems (CPS) is challenging the traditional CPS modeling approaches by violating their fundamental assumptions. However, big data also brings unique opportunities in its wake by enabling new modeling and analytics approaches as well as facilitating...

    Provided By NEC Laboratories

  • White Papers // Mar 2013

    TBF: A Memory-Efficient Replacement Policy for Flash-Based Caches

    The performance and capacity characteristics of flash storage make it attractive to use as a cache. Recency-based cache replacement policies rely on an in-memory full index, typically a B-tree or a hash table that maps each object to its recency information. Even though the recency information itself may take very...

    Provided By NEC Laboratories

  • White Papers // Nov 2012

    Device-to-Device (D2D) Communication in MU-MIMO Cellular Networks

    In this paper, the authors address a resource allocation problem, where a pair of device-to-device terminals are integrated into a Time Division Duplex (TDD) cellular network. By introducing an incremental relay transmission scheme for the D2D communication, the D2D transmitter, traditionally believed to be the source of interference, are coordinated...

    Provided By NEC Laboratories

  • White Papers // Aug 2012

    SGSA: A SDMA-OFDMA Greedy Scheduling Algorithm for WiMAX Networks

    Future wireless networks need to address the predicted growth in mobile traffic volume, expected to have an explosive growth in the next five years mainly driven by video and web applications. Transmission schemes based on Orthogonal Frequency Division Multiple Access (OFDMA) combined with Space Division Multiple Access (SDMA) techniques are...

    Provided By NEC Laboratories

  • White Papers // Jun 2012

    Coordinating Virtual MachineMigrations in Enterprise Data Centers and Clouds

    Live VM migration is being widely utilized in virtualized data centers and clouds due to its capability of maintaining high system performance under dynamic workloads. Virtual Machine (VM) migration usually requires a considerable amount of system resources such as the network bandwidth. In the case of multiple simultaneous migrations, which...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Distributed PCA-Based Anomaly Detection in Telephone Networks Through Legitimate-User Profiling

    In this paper, the authors present a distributed mechanism based on Principal Component Analysis (PCA) to profile the behavior of the legitimate users in telephone networks. The idea is to take advantage of probes distributed over the network to obtain a compact snapshot of the users they serve. A collector...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Downlink Multiuser MIMO Scheduling in LTE Advanced Systems

    In this paper, the authors consider the DownLink (DL) MultiUser (MU) Multi-Input-Multi-Output (MIMO) scheduling for the fourth generation LTE Advanced (LTE-A) cellular networks. The DL MU-MIMO scheduling can be posed as an optimization problem to maximize the weighted sum rate subject to several practical constraints, such as a per-user rank...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Improving Network Throughput in 60GHz WLANs Via Multi-AP Diversity

    Due to the limited diffracting ability of millimeter wave (mm-wave) signals, solving the blockage problem in 60GHz WLANs is one of major challenges. Since multiple Access Points (AP) are typically employed in the indoor environment to ensure the coverage and to meet the increasing demand for extremely high data rate...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Standards-Compliant LTE and LTE-A Uplink Power Control

    In LTE and LTE-Advanced uplink, the interference power in a cell depends on the user scheduling and power assignment in neighboring cells. As a result, it is hard to accurately estimate the Signal-to-Interference-plus-Noise Ratio (SINR) values and make the right MCS (Modulation and Coding Scheme) selection. To address this challenge,...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Towards Multitenancy for IO-Bound OLAP Workloads

    Consolidation of multiple databases on the same server allows service providers to save significant resources because many production database servers are often under-utilized. The authors consider the problem of minimizing the number of servers needed to host a set of tenants, while satisfying the Service Level Agreement (SLA) on the...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Two Bitcoins at the Price of One - Double-Spending Attacks on Fast Payments in Bitcoin

    Bitcoin is a decentralized payment system that is based on Proof-of-Work. Bitcoin is currently gaining popularity as a digital currency; several businesses are starting to accept Bitcoin transactions. An example case of the growing use of Bitcoin was recently reported in the media; here, Bitcoins were used as a form...

    Provided By NEC Laboratories

  • White Papers // Mar 2012

    Backhaul Resource Allocation in LTE-Advanced Relaying Systems

    In 3GPP LTE-Advanced, relay is considered as an important means for extending cell coverage and improving capacity. Backhaul resource allocation needs to be carefully designed to achieve the performance advantage of relay. In this paper, the authors propose a two-step backhaul resource allocation scheme for an in-band relaying system based...

    Provided By NEC Laboratories

  • White Papers // Feb 2012

    Optimizing Data Warehousing Applications for GPUs Using Kernel Fusion/Fission

    Data warehousing applications represent an emergent application arena that requires the processing of relational queries and computations over massive amounts of data. Modern general purpose GPUs are high core count architectures that potentially offer substantial improvements in throughput for these applications. However, there are significant challenges that arise due to...

    Provided By NEC Laboratories

  • White Papers // Jul 2011

    Towards Holistic Multi-Tenant Monitoring for Virtual Data Centers

    Cloud computing becomes increasingly prevalent for outsourcing IT functions. The basic feature of offering virtual data center slices to customers has been in use for some time now. So far, customers only get the raw resources, with only little insight and control of their resources. But to let customers build...

    Provided By NEC Laboratories

  • White Papers // Apr 2011

    Reasoning about Threads with Bounded Lock Chains

    With the increasing prevalence of multi-core processors and concurrent multi-threaded software, it is highly critical that dataflow analysis for concurrent programs, similar to the ones for the sequential domain, be developed. For sequential programs, Push-Down Systems (PDSs) have emerged as a powerful, unifying framework for efficiently encoding many inter-procedural dataflow...

    Provided By NEC Laboratories

  • White Papers // Feb 2011

    Identities in the Future Internet of Things

    There are two problem areas of the current Internet to be solved in Future Internet scenarios - security and putting the user back in control despite the move to the Internet of things. With this in mind, the authors address problems associated with the diversifying of the Internet towards an...

    Provided By NEC Laboratories

  • White Papers // Dec 2010

    CloudDB: A Data Store for All Sizes in the Cloud

    The authors present a vision for a comprehensive data management platform in the cloud. The envisioned system, called CloudDB, would provide data management capabilities as a service to transparently and efficiently support diverse application workloads with identifiable SLA guarantees and end-to-end system management functions. The system will be able to...

    Provided By NEC Laboratories

  • White Papers // Dec 2010

    Emulating Goliath Storage Systems with David

    Benchmarking file and storage systems on large file-system images is important, but difficult and often infeasible. Typically, running benchmarks on such large disk setups is a frequent source of frustration for file-system evaluators; the scale alone acts as a strong deterrent against using larger albeit realistic benchmarks. To address this...

    Provided By NEC Laboratories

  • White Papers // May 2010

    Identity Driven Mobility Architecture

    This paper describes an identity based mobility architecture, which relies on the Identity Management System for mobility decision and execution. This is achieved by clearly separating mobility into a two step procedure: decision and action. The decisions are outsourced on the Identity plane, while the action (moving) is carried out...

    Provided By NEC Laboratories

  • White Papers // Jul 2009

    IntelligentWorkload Factoring for a Hybrid Cloud Computing Model

    The authors present an intelligent workload factoring service for enterprise customers to make the best use of public cloud services along with their privately-owned (legacy) data centers. It enables federation between on- and off-premise infrastructures for hosting Internet-based applications, and the intelligence lies in the explicit segregation of base workload...

    Provided By NEC Laboratories

  • White Papers // May 2010

    Identity Driven Mobility Architecture

    This paper describes an identity based mobility architecture, which relies on the Identity Management System for mobility decision and execution. This is achieved by clearly separating mobility into a two step procedure: decision and action. The decisions are outsourced on the Identity plane, while the action (moving) is carried out...

    Provided By NEC Laboratories

  • White Papers // Feb 2011

    Identities in the Future Internet of Things

    There are two problem areas of the current Internet to be solved in Future Internet scenarios - security and putting the user back in control despite the move to the Internet of things. With this in mind, the authors address problems associated with the diversifying of the Internet towards an...

    Provided By NEC Laboratories

  • White Papers // Aug 2012

    SGSA: A SDMA-OFDMA Greedy Scheduling Algorithm for WiMAX Networks

    Future wireless networks need to address the predicted growth in mobile traffic volume, expected to have an explosive growth in the next five years mainly driven by video and web applications. Transmission schemes based on Orthogonal Frequency Division Multiple Access (OFDMA) combined with Space Division Multiple Access (SDMA) techniques are...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Distributed PCA-Based Anomaly Detection in Telephone Networks Through Legitimate-User Profiling

    In this paper, the authors present a distributed mechanism based on Principal Component Analysis (PCA) to profile the behavior of the legitimate users in telephone networks. The idea is to take advantage of probes distributed over the network to obtain a compact snapshot of the users they serve. A collector...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Downlink Multiuser MIMO Scheduling in LTE Advanced Systems

    In this paper, the authors consider the DownLink (DL) MultiUser (MU) Multi-Input-Multi-Output (MIMO) scheduling for the fourth generation LTE Advanced (LTE-A) cellular networks. The DL MU-MIMO scheduling can be posed as an optimization problem to maximize the weighted sum rate subject to several practical constraints, such as a per-user rank...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Improving Network Throughput in 60GHz WLANs Via Multi-AP Diversity

    Due to the limited diffracting ability of millimeter wave (mm-wave) signals, solving the blockage problem in 60GHz WLANs is one of major challenges. Since multiple Access Points (AP) are typically employed in the indoor environment to ensure the coverage and to meet the increasing demand for extremely high data rate...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Standards-Compliant LTE and LTE-A Uplink Power Control

    In LTE and LTE-Advanced uplink, the interference power in a cell depends on the user scheduling and power assignment in neighboring cells. As a result, it is hard to accurately estimate the Signal-to-Interference-plus-Noise Ratio (SINR) values and make the right MCS (Modulation and Coding Scheme) selection. To address this challenge,...

    Provided By NEC Laboratories

  • White Papers // Mar 2012

    Backhaul Resource Allocation in LTE-Advanced Relaying Systems

    In 3GPP LTE-Advanced, relay is considered as an important means for extending cell coverage and improving capacity. Backhaul resource allocation needs to be carefully designed to achieve the performance advantage of relay. In this paper, the authors propose a two-step backhaul resource allocation scheme for an in-band relaying system based...

    Provided By NEC Laboratories

  • White Papers // Feb 2012

    Optimizing Data Warehousing Applications for GPUs Using Kernel Fusion/Fission

    Data warehousing applications represent an emergent application arena that requires the processing of relational queries and computations over massive amounts of data. Modern general purpose GPUs are high core count architectures that potentially offer substantial improvements in throughput for these applications. However, there are significant challenges that arise due to...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Two Bitcoins at the Price of One - Double-Spending Attacks on Fast Payments in Bitcoin

    Bitcoin is a decentralized payment system that is based on Proof-of-Work. Bitcoin is currently gaining popularity as a digital currency; several businesses are starting to accept Bitcoin transactions. An example case of the growing use of Bitcoin was recently reported in the media; here, Bitcoins were used as a form...

    Provided By NEC Laboratories

  • White Papers // Nov 2012

    Device-to-Device (D2D) Communication in MU-MIMO Cellular Networks

    In this paper, the authors address a resource allocation problem, where a pair of device-to-device terminals are integrated into a Time Division Duplex (TDD) cellular network. By introducing an incremental relay transmission scheme for the D2D communication, the D2D transmitter, traditionally believed to be the source of interference, are coordinated...

    Provided By NEC Laboratories

  • White Papers // Jul 2009

    IntelligentWorkload Factoring for a Hybrid Cloud Computing Model

    The authors present an intelligent workload factoring service for enterprise customers to make the best use of public cloud services along with their privately-owned (legacy) data centers. It enables federation between on- and off-premise infrastructures for hosting Internet-based applications, and the intelligence lies in the explicit segregation of base workload...

    Provided By NEC Laboratories

  • White Papers // Jul 2011

    Towards Holistic Multi-Tenant Monitoring for Virtual Data Centers

    Cloud computing becomes increasingly prevalent for outsourcing IT functions. The basic feature of offering virtual data center slices to customers has been in use for some time now. So far, customers only get the raw resources, with only little insight and control of their resources. But to let customers build...

    Provided By NEC Laboratories

  • White Papers // Feb 2014

    A Case for a Flexible Scalar Unit in SIMT Architecture

    The wide availability and the Single-Instruction Multiple-Thread (SIMT)-style programming model have made Graphics Processing Units (GPUs) a promising choice for high performance computing. However, because of the SIMT style processing, an instruction will be executed in every thread even if the operands are identical for all the threads. To overcome...

    Provided By NEC Laboratories

  • White Papers // May 2013

    Transparent and Flexible Network Management for Big Data Processing in the Cloud

    The authors introduce FlowComb, a network management framework that helps big data processing applications, such as Hadoop, achieve high utilization and low data processing times. FlowComb predicts application network transfers, sometimes before they start, by using software agents installed on application servers and while remaining completely transparent to the application....

    Provided By NEC Laboratories

  • White Papers // Jun 2012

    Coordinating Virtual MachineMigrations in Enterprise Data Centers and Clouds

    Live VM migration is being widely utilized in virtualized data centers and clouds due to its capability of maintaining high system performance under dynamic workloads. Virtual Machine (VM) migration usually requires a considerable amount of system resources such as the network bandwidth. In the case of multiple simultaneous migrations, which...

    Provided By NEC Laboratories

  • White Papers // May 2013

    Modeling and Analytics for Cyber-Physical Systems in the Age of Big Data

    In this paper, the authors argue that the availability of \"Big\" monitoring data on Cyber-Physical Systems (CPS) is challenging the traditional CPS modeling approaches by violating their fundamental assumptions. However, big data also brings unique opportunities in its wake by enabling new modeling and analytics approaches as well as facilitating...

    Provided By NEC Laboratories

  • White Papers // May 2013

    Mobile Data Sync in a Blink

    Mobile applications are becoming increasingly datacentric - often relying on cloud services to store, share, and analyze data. App developers have to frequently manage the local storage on the device (e.g., SQLite databases and file systems), as well as data synchronization with cloud services. Developers have to address common issues...

    Provided By NEC Laboratories

  • White Papers // Mar 2013

    TBF: A Memory-Efficient Replacement Policy for Flash-Based Caches

    The performance and capacity characteristics of flash storage make it attractive to use as a cache. Recency-based cache replacement policies rely on an in-memory full index, typically a B-tree or a hash table that maps each object to its recency information. Even though the recency information itself may take very...

    Provided By NEC Laboratories

  • White Papers // Dec 2010

    Emulating Goliath Storage Systems with David

    Benchmarking file and storage systems on large file-system images is important, but difficult and often infeasible. Typically, running benchmarks on such large disk setups is a frequent source of frustration for file-system evaluators; the scale alone acts as a strong deterrent against using larger albeit realistic benchmarks. To address this...

    Provided By NEC Laboratories

  • White Papers // Jul 2013

    Building a Delay-Tolerant Cloud for Mobile Data

    Mobile data usage is on a tremendous rise, due not only to increasing number of users but also to an increase in the number of applications that transfer data over the network. Moreover, applications for sharing, sensing, and collaboration have become more popular, causing significant amounts of data to be...

    Provided By NEC Laboratories

  • White Papers // Apr 2011

    Reasoning about Threads with Bounded Lock Chains

    With the increasing prevalence of multi-core processors and concurrent multi-threaded software, it is highly critical that dataflow analysis for concurrent programs, similar to the ones for the sequential domain, be developed. For sequential programs, Push-Down Systems (PDSs) have emerged as a powerful, unifying framework for efficiently encoding many inter-procedural dataflow...

    Provided By NEC Laboratories

  • White Papers // Dec 2010

    CloudDB: A Data Store for All Sizes in the Cloud

    The authors present a vision for a comprehensive data management platform in the cloud. The envisioned system, called CloudDB, would provide data management capabilities as a service to transparently and efficiently support diverse application workloads with identifiable SLA guarantees and end-to-end system management functions. The system will be able to...

    Provided By NEC Laboratories

  • White Papers // May 2012

    Towards Multitenancy for IO-Bound OLAP Workloads

    Consolidation of multiple databases on the same server allows service providers to save significant resources because many production database servers are often under-utilized. The authors consider the problem of minimizing the number of servers needed to host a set of tenants, while satisfying the Service Level Agreement (SLA) on the...

    Provided By NEC Laboratories