Carnegie Mellon University

Displaying 1-40 of 538 results

  • White Papers // Feb 2014

    SpringFS: Bridging Agility and Performance in Elastic Distributed Storage

    The elastic storage systems can be expanded or contracted to meet current demand, allowing servers to be turned off or used for other tasks. However, the usefulness of an elastic distributed storage system is limited by its agility: how quickly it can increase or decrease its number of servers. Due...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2014

    Toward Strong, Usable Access Control for Shared Distributed Data

    As non-expert users produce increasing amounts of personal digital data, usable access control becomes critical. Current approaches often fail, because they insufficiently protect data or confuse users about policy specification. This paper presents penumbra, a distributed file system with access control designed to match users' mental models while providing principled...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2014

    Improving Cache Performance by Exploiting Read-Write Disparity

    Cache read misses stall the processor if there are no independent instructions to execute. In contrast, most cache write misses are off the critical path of execution, since writes can be buffered in the cache or the store buffer. With few exceptions, cache lines that serve loads are more critical...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2014

    Agentless Cloud-wide Streaming of Guest File System Updates

    The authors propose a non-intrusive approach for monitoring Virtual Machines (VMs) in the cloud. At the core of this approach is a mechanism for selective real-time monitoring of guest file updates within VM instances. This mechanism is agentless, requiring no guest VM support. It has low virtual I/O overhead, low...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2014

    Improving DRAM Performance by Parallelizing Refreshes with Accesses

    Modern main memory is predominantly built using Dynamic Random Access Memory (DRAM) cells. A DRAM cell consists of a capacitor to store one bit of data as electrical charge. The capacitor leaks charge over time, causing stored data to change. As a result, DRAM requires an operation called refresh that...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2014

    ARP Attacks in Wireless Ad Hoc Networks

    Previous research to secure ad hoc network protocols concentrates on key distribution and on securing the routing protocol. Unfortunately, securing the routing layer is not sufficient to secure the ad hoc network, as lower layer and upper layer communication protocols remain vulnerable to attack. In this paper, the authors illustrate...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2014

    Matching Database Access Patterns to Storage Characteristics

    Database storage managers employ sophisticated algorithms attempting to exploit the performance available inside today's storage systems. However, because the communication between the Storage Manager (SM) and a storage device is limited by a high-level protocol, both the SM and the device make decisions largely in isolation and do not realize...

    Provided By Carnegie Mellon University

  • White Papers // Dec 2013

    Tetrisched: Space-Time Scheduling for Heterogeneous Datacenters

    Tetrisched is a new scheduler that explicitly considers both job-specific preferences and estimated job runtimes in its allocation of resources. Combined, this information allows tetrisched to provide higher overall value to complex application mixes consolidated on heterogeneous collections of machines. Job-specific preferences, provided by tenants in the form of composable...

    Provided By Carnegie Mellon University

  • White Papers // Nov 2013

    More Effective Distributed ML via a Stale Synchronous Parallel Parameter Server

    The authors propose a parameter server system for distributed ML, which follows a Stale Synchronous Parallel (SSP) model of computation that maximizes the time computational workers spend doing useful work on ML algorithms, while still providing correctness guarantees. The parameter server provides an easy-to-use shared interface for read/write access to...

    Provided By Carnegie Mellon University

  • Webcasts // Nov 2013

    Illicit Cyber Activity Involving Fraud

    In this webcast, the presenter going to explain about illicit cyber activity involving fraud from the virtual event managing the insider threat. the presenters aim is to assist organizations in improving their security posture and incident response capability by researching technical threat areas, developing and conducting information security assessments, and...

    Provided By Carnegie Mellon University

  • Webcasts // Nov 2013

    Engineering Realistic Synthetic Insider Threat (Cyber-Social) Test Data

    Access to data remains a significant impediment to advancing the science of insider threat research. In this webcast, the presenter going to explain about engineering realistic synthetic about the insider threat test data from the virtual event who manages the insider threat.

    Provided By Carnegie Mellon University

  • Webcasts // Nov 2013

    Emerging Trends

    An emerging trend to pay attention to is the malicious outsider taking advantage of an inadvertent insider. In this webcast, the presenter going to explain about emerging trends in insider threat research from the virtual event managing the insider threat.

    Provided By Carnegie Mellon University

  • Webcasts // Nov 2013

    Best Practices and Controls for Mitigating Insider Threats

    Threats can stem from simple activities like uploading, emailing, and posting sensitive data, etc. In this webcast, the presenter will explain about best practices and controls for mitigating insider threats from the virtual event of how to manage the insider threat.

    Provided By Carnegie Mellon University

  • Webcasts // Nov 2013

    Panel Discussion: Managing the Insider Threat: What Every Organization Should Know

    In this webcast, the presenter going to discuss about managing the insider threat and how to ensure the protection of and appropriate access to intellectual property and other critical assets, systems, and data.

    Provided By Carnegie Mellon University

  • Podcasts // Nov 2013

    Overview of the Threat Posed by Insiders to Critical Assets

    Insiders pose a substantial threat by virtue of their knowledge of and access to the users systems and/or their databases. In this webcast, the presenter will give an overview of the threat posed by insiders to critical assets.

    Provided By Carnegie Mellon University

  • White Papers // Oct 2013

    GOTCHA Password Hackers!

    The authors introduce GOTCHAs (Generating panOptic Turing tests to tell Computers and Humans Apart) as a way of preventing automated offline dictionary attacks against user selected passwords. A GOTCHA is a randomized puzzle generation protocol, which involves interaction between a computer and a human. Informally, a GOTCHA should satisfy two...

    Provided By Carnegie Mellon University

  • White Papers // Oct 2013

    Challenges in Security and Privacy for Mobile Edge-Clouds

    Mobile devices such as Smartphone and tablets are ubiquitous today, and many of them possess significant computation power, powerful sensors such as high-resolution cameras and GPS sensors, and a wealth of sensor data such as photos, videos, and location information. Collections of mobile devices in close geographical proximity present both...

    Provided By Carnegie Mellon University

  • White Papers // Sep 2013

    LightTx: A Lightweight Transactional Design in Flash-based SSDs to Support Flexible Transactions

    Flash memory has accelerated the architectural evolution of storage systems with its unique characteristics compared to magnetic disks. The no-overwrite property of flash memory has been leveraged to efficiently support transactions, a commonly used mechanism in systems to provide consistency. However, existing transaction designs embedded in flash-based Solid State Drives...

    Provided By Carnegie Mellon University

  • White Papers // Sep 2013

    Program Interference in MLC NAND Flash Memory: Characterization, Modeling, and Mitigation

    As NAND flash memory continues to scale down to smaller process technology nodes, its reliability and endurance are degrading. One important source of reduced reliability is the phenomenon of program interference: when a flash cell is programmed to a value, the programming operation affects the threshold voltage of not only...

    Provided By Carnegie Mellon University

  • White Papers // Sep 2013

    HAT: Heterogeneous Adaptive Throttling for On-Chip Networks

    The Network-on-Chip (NoC) is a primary shared resource in a Chip Multi-Processor (CMP) system. As core counts continue to increase and applications become increasingly data-intensive, the network load will also increase, leading to more congestion in the network. This network congestion can degrade system performance if the network load is...

    Provided By Carnegie Mellon University

  • White Papers // Sep 2013

    Secure Two-Party Computation with Reusable Bit-Commitments, via A Cut-and-Choose with Forge-and-Lose Technique

    A Secure Two-Party Computation (S2PC) protocol allows two parties to compute over their combined private inputs, as if inter-mediated by a trusted third party. In the active model, security is maintained even if one party is malicious, deviating from the protocol specification. For example, an honest party retains privacy of...

    Provided By Carnegie Mellon University

  • White Papers // Aug 2013

    Design of a Write-Optimized Data Store

    The WriteBuffer (WB) tree is a new write-optimized data structure that can be used to implement per-node storage in unordered key-value stores. The WB tree provides faster writes than the Log-Structured Merge (LSM) tree that is used in many current high-performance key-value stores. It achieves this by replacing compactions in...

    Provided By Carnegie Mellon University

  • Webcasts // Aug 2013

    Observations of Successful Cyber Security Operations

    In this Webcast, the presenter going explain about the cyber security The presenter will also discuss the observations of successful cyber security operations from the virtual event showing the users a big picture about the organization how they successfully react to new specific accessories build on the cyber security.

    Provided By Carnegie Mellon University

  • Webcasts // Aug 2013

    Responding to a Large Scale Cybersecurity Incident

    In this Webcast, the presenter explain about how to respond to a large scale cyber security incidents, with an introduction about the role of technology. Technology which is an important one, but the limitations of that need to be understood.

    Provided By Carnegie Mellon University

  • Webcasts // Aug 2013

    20+ Years of Cyber (in)Security

    The use of information and communications technology is pervasive. The information systems are increasingly interconnected and interdependent. Attack technology is outpacing defensive technology. In this webcast, the presenter will give an introduction to the cyber security.

    Provided By Carnegie Mellon University

  • Webcasts // Aug 2013

    Achieving Mission Assurance Through Resilience Management

    In this webcast, the presenter going to explain about the resilience management. Resilience management is to protect a sustain organizations mission and business operations. The presenter will also explain about how the organizations are constant operational stress on these days.

    Provided By Carnegie Mellon University

  • Webcasts // Aug 2013

    Developing Your Cyber Workforce

    In this webcast, the presenter going to explain about the how to develop the cyber workforce against the security attacks. The presenter going to discuss about the new solutions and research that he had done to improve the security.

    Provided By Carnegie Mellon University

  • White Papers // Aug 2013

    A Proof of Correctness for Egalitarian Paxos

    In this paper the authors present a proof of correctness for Egalitarian Paxos (EPaxos), a new distributed consensus algorithm based on Paxos. EPaxos achieves three goals: availability without interruption as long as a simple majority of replicas are reachable - its availability is not interrupted when replicas crash or fail...

    Provided By Carnegie Mellon University

  • White Papers // Aug 2013

    Breaking the DDoS Attack Chain

    Department of Defense (DoD) communications and data networks continue to be targets for adversaries to deny operational use of those networks. Distributed Denial of Service (DDoS) is one such attack strategy that has proven to be an effective method of denying service to military, political, infrastructure, and economic targets. The...

    Provided By Carnegie Mellon University

  • Webcasts // Aug 2013

    The Cyber Security R&D Pipeline - Building Capability Through Science

    In this webcast, the presenter going to explain about the cyber security R&D pipeline how to build the capability through science. The presenter explains about the SEI advances software engineering and related disciplines to ensure systems with predictable and improved quality, cost and schedule.

    Provided By Carnegie Mellon University

  • White Papers // Jul 2013

    ReDABLS: Revisiting Device Attestation with Bounded Leakage of Secrets

    Many commodity operating systems and applications become infested with malicious software over time, primarily due to exploits that take advantage of software flaws and operator errors. In this paper, the authors present the salient features of a system design which allows remote-device authentication by a verifier, reaching malware-free system states,...

    Provided By Carnegie Mellon University

  • White Papers // Jun 2013

    A Case for Efficient Hardware/Software Cooperative Management of Storage and Memory

    Most applications manipulate persistent data, yet traditional systems decouple data manipulation from persistence in a two-level storage model. Programming languages and system software manipulate data in one set of formats in volatile main memory (DRAM) using a load/store interface, while storage systems maintain persistence in another set of formats in...

    Provided By Carnegie Mellon University

  • White Papers // Jun 2013

    Memory Scaling: A Systems Architecture Perspective

    The memory system is a fundamental performance and energy bottleneck in almost all computing systems. Recent system design, application, and technology trends that require more capacity, bandwidth, efficiency, and predictability out of the memory system make it an even more important system bottleneck. At the same time, DRAM technology is...

    Provided By Carnegie Mellon University

  • White Papers // Jun 2013

    Space-Efficient, High-Performance Rank & Select Structures on Uncompressed Bit Sequences

    Rank & select data structures are one of the fundamental building blocks for many modern succinct data structures. With the continued growth of massive-scale information services, the space efficiency of succinct data structures is becoming increasingly attractive in practice. In this paper, the authors re-examine the design of rank &...

    Provided By Carnegie Mellon University

  • White Papers // May 2013

    Resistance is Not Futile: Detecting DDoS Attacks without Packet Inspection

    Packets in anonymous networks are fully protected. Therefore, traditional methods relying on packet header and higher layer information do not work to detect Distributed-Denial-of-Service (DDoS) attacks in anonymous networks. In this paper, the authors propose to use observable statistics at routers that need no packet inspection to infer the presence...

    Provided By Carnegie Mellon University

  • White Papers // May 2013

    UnLocIn: Unauthorized Location Inference on Smartphones without Being Caught

    Location privacy has become one of the critical issues in the Smartphone era. Since users carry their phones everywhere and all the time, leaking users' location information can have dangerous implications. In this paper, the authors leverage the idea that Wi-Fi parameters not considered to be \"Sensitive\" in the Android...

    Provided By Carnegie Mellon University

  • White Papers // May 2013

    Network Self-Organization in the Internet of Things

    The Internet of Things is a paradigm that allows the interaction of ubiquitous devices through a network to achieve common goals. This paradigm like any man-made infrastructure is subject to disasters, outages and other adversarial conditions. Under these situations provisioned communications fail, rendering this paradigm with little or no use....

    Provided By Carnegie Mellon University

  • White Papers // May 2013

    How to Jam Without Getting Caught: Analysis and Empirical Study of Stealthy Periodic Jamming

    Despite the widespread commercial use of spread spectrum technology, advanced algorithms and modern hardware capabilities still allows efficient denial-of-service attacks against wireless communication systems using jamming. Much of the recent work on jamming mitigation has focused on how to adjust the transmitter-receiver system once a jamming attack has been detected....

    Provided By Carnegie Mellon University

  • White Papers // May 2013

    ASIA: Accelerated Secure In-network Aggregation in Vehicular Sensing Networks

    Vehicular Ad-Hoc NETworks (VANETs) can potentially become a sensing platform. In-network aggregation, a fundamental primitive for querying sensory data, has been shown to reduce overall communication overhead at large. To secure data aggregation in VANETs, existing schemes mainly rely on digital signatures. However, generating and verifying such signatures can cause...

    Provided By Carnegie Mellon University

  • White Papers // May 2013

    Stochastic Optimization of Flow-Jamming Attacks in Multichannel Wireless Networks

    An attacker can launch an efficient jamming attack to deny service to flows in wireless networks by using cross-layer knowledge of the target network. For example, flow-jamming defined in existing work incorporates network layer information into the conventional jamming attack to maximize its attack efficiency. In this paper, the authors...

    Provided By Carnegie Mellon University

  • White Papers // Mar 2012

    Enabling Efficient and Scalable Hybrid Memories Using Fine-Granularity DRAM Cache Management

    Hybrid main memories composed of DRAM as a cache to scalable non-volatile memories such as Phase-Change Memory (PCM) can provide much larger storage capacity than traditional main memories. A key challenge for enabling high-performance and scalable hybrid memories, though, is efficiently managing the metadata (e.g., tags) for data cached in...

    Provided By Carnegie Mellon University

  • White Papers // Oct 2011

    Collaborating With Executable Content Across Space and Time

    Executable content is of growing importance in many domains. How does one share and archive such content at Internet-scale for spatial and temporal collaboration? Spatial collaboration refers to the classic concept of user collaboration: two or more users who are at different Internet locations performing a task using shared context....

    Provided By Carnegie Mellon University

  • White Papers // Jul 2012

    STIR-Ing the Wireless Medium With Self-Tuned, Inference-Based, Real-Time Jamming

    Jamming, broadcasting to intentionally interfere with wireless reception has long been a problem for wireless systems. Recent research demonstrates numerous advances in jamming techniques that increase attack efficiency or reduce the probability an attack will be detected by choosing attack parameters based on a system's configuration. In this paper, the...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2012

    A Comparative Study of Location-sharing Privacy Preferences in the U.S. and China

    While prior studies have provided users with an initial understanding of people's location-sharing privacy preferences, they have been limited to Western countries and have not investigated the impact of the granularity of location disclosures on people's privacy preferences. The authors report findings of a three-week comparative study collecting location traces...

    Provided By Carnegie Mellon University

  • White Papers // Nov 2012

    So Near, and Yet so Far: Managing "far-Away" Interferers in Dense Femto-Cell Networks

    The authors expect femto-cells to be massively and densely deployed in the future. Numerous existing works on femto-cell interference management assume that the local topology of interfering femto-cells can be sufficiently approximated through sensing, if not already known in advance. They show that this assumption results in poor throughput performance...

    Provided By Carnegie Mellon University

  • White Papers // Oct 2012

    Chronological Examination of Insider Threat Sabotage: Preliminary Observations

    An employee of a telecommunications company, when asked to resign, responded by sabotaging company IT systems, shutting down their telecommunication system and blocking 911 services in four major cities. A disgruntled former employee, upset that he was not hired for a full-time position, remotely accessed SCADA systems for a sewage...

    Provided By Carnegie Mellon University

  • White Papers // Oct 2010

    Initial Findings for Provisioning Variation in Cloud Computing

    Cloud computing offers a paradigm shift in management of computing resources for large-scale applications. Using the Infrastructure-as-a-service (IaaS) cloud computing model, users today can request dynamically provisioned, virtualized resources such as CPU, memory, disk, and network access in the form of virtualized resources. The client typically requests resources based on...

    Provided By Carnegie Mellon University

  • White Papers // May 2012

    Center-of-Gravity Reduce Task Scheduling to Lower MapReduce Network Traffic

    MapReduce is by far one of the most successful realizations of large-scale data-intensive cloud computing platforms. MapReduce automatically parallelizes computation by running multiple map and/or reduce tasks over distributed data across multiple machines. Hadoop is an open source implementation of MapReduce. When Hadoop schedules reduce tasks, it neither exploits data...

    Provided By Carnegie Mellon University

  • White Papers // Oct 2011

    Locality-Aware Reduce Task Scheduling for Mapreduce

    MapReduce offers a promising programming model for big data processing. Inspired by functional languages, MapReduce allows programmers to write functional-style code which gets automatically divided into multiple map and/or reduce tasks and scheduled over distributed data across multiple machines. Hadoop, an open source implementation of MapReduce, schedules map tasks in...

    Provided By Carnegie Mellon University

  • White Papers // Nov 2011

    Votus: A Flexible and Scalable Monitoring Framework for Virtualized Clusters

    Large-scale distributed processing frameworks such as Hadoop are currently enjoying wide popularity for big data computation. Performance Analysis and monitoring under these frameworks are inherently difficult especially in a virtualized environment. Existing distributed monitoring tools can only report virtual resource usage. Such reported information might be insufficient for developers and...

    Provided By Carnegie Mellon University

  • White Papers // Feb 2011

    Teaching the Cloud

    Cloud computing is a disruptive technology, one that embodies a major conceptual shift and is rapidly changing the way users, developers, and organizations work with computing infrastructure. Carnegie Mellon University in Qatar offered a one-semester undergraduate course to introduce students to cloud computing. In this paper, the authors describe their...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2012

    D-ADMM: A Distributed Algorithm for Compressed Sensing and Other Separable Optimization Problems

    The authors propose a distributed, decentralized algorithm for solving separable optimization problems over a connected network of compute nodes. In a separable problem, each node has its own private function and its own private constraint set. Private means that no other node has access to it. The goal is to...

    Provided By Carnegie Mellon University

  • White Papers // Feb 2011

    Cooperative Convex Optimization in Networked Systems: Augmented Lagrangian Algorithms With Directed Gossip Communication

    Recently, there has been increased interest in large scale networked systems including networks of agents, wireless ad-hoc networks, and Wireless Sensor Networks (WSNs.) Typically, these systems lack a central unit, and the inter-node communication is prone to random failures (e.g., random packet dropouts in WSNs.) In this paper, the authors...

    Provided By Carnegie Mellon University

  • White Papers // Jun 2012

    TACHYON: Tandem Execution for Efficient Live Patch Testing

    The vast number of security incidents are caused by exploits against vulnerabilities for which a patch is already available, but that users simply did not install. Patch installation is often delayed because patches must be tested manually to make sure they do not introduce problems, especially at the enterprise level....

    Provided By Carnegie Mellon University

  • White Papers // Jun 2012

    How Does Your Password Measure Up? the Effect of Strength Meters on Password Creation

    To help users create stronger text-based passwords, many web sites have deployed password meters that provide visual feedback on password strength. Although these meters are in wide use, their effects on the security and usability of passwords have not been well studied. The authors present a 2,931-subject study of password...

    Provided By Carnegie Mellon University

  • White Papers // May 2013

    Geometry-Based Vehicle-to-Vehicle Channel Modeling for Large-Scale Simulation

    Large-scale Vehicular Ad Hoc NETwork (VANET) simulators by and large employ simple statistical channel models. By design, such models do not account for specific objects in the region of interest when estimating the channel. While computationally efficient, these models were shown to be unable to provide satisfactory accuracy on a...

    Provided By Carnegie Mellon University

  • White Papers // Apr 2013

    KISS: "Key It Simple and Secure" Corporate Key Management

    Deploying a corporate key management system faces fundamental challenges, such as fine-grained key usage control and secure system administration. None of the current commercial systems (either based on software or hardware security modules) or research proposals adequately address both challenges with small and simple Trusted Computing Base (TCB). This paper...

    Provided By Carnegie Mellon University

  • White Papers // Apr 2013

    Design, Implementation and Verification of an EXtensible and Modular Hypervisor Framework

    The authors present the design, implementation, and verification of XMHF - an eXtensible and Modular Hypervisor Framework. XMHF is designed to achieve three goals - modular extensibility, automated verification, and high performance. XMHF includes a core that provides functionality common to many hypervisor-based security architectures and supports extensions that augment...

    Provided By Carnegie Mellon University

  • White Papers // Sep 2011

    SAV-V: Securing Anti-Virus with Virtualization

    Today's desktop PCs rely on security software such as anti-virus products and personal firewalls for protection. Unfortunately, malware authors have adapted by specifically targeting and disabling these defenses, a practice exacerbated by the rise in zero-day exploits. In this paper, the authors present the design, implementation, and evaluation of SAV-V,...

    Provided By Carnegie Mellon University

  • White Papers // Nov 2011

    Towards a Software Framework for Automatic Business Process Redesign

    A key element to the success of any organization is the ability to continuously improve its business process performance. Efficient Business Process Redesign (BPR) methodologies are needed to allow organizations to face the changing business conditions. For a long time, practices for BPR were done case-by-case and were based on...

    Provided By Carnegie Mellon University

  • White Papers // Nov 2012

    Theia: Visual Signatures for Problem Diagnosis in Large Hadoop Clusters

    Diagnosing performance problems in large distributed systems can be daunting as the copious volume of monitoring information available can obscure the root-cause of the problem. Automated diagnosis tools help narrow down the possible root-causes - however, these tools are not perfect thereby motivating the need for visualization tools that allow...

    Provided By Carnegie Mellon University

  • White Papers // Sep 2012

    Transparent System Call Based Performance Debugging for Cloud Computing

    Problem diagnosis and debugging in distributed environments such as the cloud and popular distributed systems frameworks has been a hard problem. The authors explore an evaluation of a novel way of debugging distributed systems, such as the MapReduce framework, by using system calls. Performance problems in such systems can be...

    Provided By Carnegie Mellon University

  • White Papers // Dec 2011

    Statistical Learning for File-Type Identification

    File-Type Identification (FTI) is an important problem in digital forensics, intrusion detection, and other related fields. Using state-of-the-art classification techniques to solve FTI problems has begun to receive research attention; however, general conclusions have not been reached due to the lack of thorough evaluations for method comparison. This paper presents...

    Provided By Carnegie Mellon University

  • White Papers // Sep 2012

    Street-Level Trust Semantics for Attribute Authentication

    The problem of determining whether a receiver may safely accept attributes (e.g., identity, credentials, location) of unknown senders in various online social protocols is a special instance of a more general problem of establishing trust in interactive protocols. The authors introduce the notion of interactive trust protocols to illustrate the...

    Provided By Carnegie Mellon University

  • White Papers // May 2012

    Saving Cash by Using Less Cache

    With the advent of cloud computing, web service providers have the ability to dynamically scale their computing infrastructures to match demand. Further, because cloud resources are often priced per-use, web service providers have a monetary incentive to minimize the number of resources consumed while still meeting the Service Level Agreements...

    Provided By Carnegie Mellon University

  • White Papers // Apr 2012

    RAIDR: Retention-Aware Intelligent DRAM Refresh

    Dynamic Random-Access Memory (DRAM) is the building block of modern main memory systems. DRAM cells must be periodically refreshed to prevent loss of data. These refresh operations waste energy and degrade system performance by interfering with memory accesses. The negative effects of DRAM refresh increase as DRAM device capacity increases....

    Provided By Carnegie Mellon University

  • White Papers // Apr 2012

    A Case for Exploiting Subarray-Level Parallelism (SALP) in DRAM

    Modern DRAMs have multiple banks to serve multiple memory requests in parallel. However, when two requests go to the same bank, they have to be served serially, exacerbating the high latency of off-chip memory. Adding more banks to the system to mitigate this problem incurs high system cost. The authors'...

    Provided By Carnegie Mellon University

  • White Papers // Apr 2012

    Staged Memory Scheduling: Achieving High Performance and Scalability in Heterogeneous Systems

    When multiple processor (CPU) cores and a GPU integrated together on the same chip share the off-chip main memory, requests from the GPU can heavily interfere with requests from the CPU cores, leading to low system performance and starvation of CPU cores. Unfortunately, state-of-the-art application-aware memory scheduling algorithms are ineffective...

    Provided By Carnegie Mellon University

  • White Papers // Mar 2012

    MinBD: Minimally-Buffered Deflection Routing for Energy-Efficient Interconnect

    A conventional Network-on-Chip (NoC) router uses input buffers to store in-flight packets. These buffers improve performance, but consume significant power. It is possible to bypass these buffers when they are empty, reducing dynamic power, but static buffer power, and dynamic power when buffers are utilized, remains. To improve energy efficiency,...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2012

    How Close Is Close Enough ? Understanding the Role of Cloudlets in Supporting Display Appropriation by Mobile Users

    Transient use of displays by mobile users was prophesied two decades ago. Today, convergence of a range of technologies enables the realization of this vision. For researchers in this space, one key question is where to physically locate the application for which the display has been appropriated. The emergence of...

    Provided By Carnegie Mellon University

  • White Papers // Nov 2012

    A Case for Scaling HPC Metadata Performance Through De-Specialization

    Lack of a highly scalable and parallel metadata service is the Achilles heel for many cluster file system deployments in both the HPC world and the Internet services world. This is because most cluster file systems have focused on scaling the data path, i.e. providing high bandwidth parallel I/O to...

    Provided By Carnegie Mellon University

  • White Papers // Sep 2010

    Anomalies in Optimal Rate-Control and Scheduling Protocols for Cognitive Radio Networks

    Protocols in Cognitive Radio Networks (CRNs) tune the radio and network parameters to utilize the unused frequency spectrum, and thus improve the application performance. Generalized Network Utility Maximization (GNUM) approach has been used to derive optimal algorithms in CRN from a theoretical formulation of the problem. However, there are several...

    Provided By Carnegie Mellon University

  • White Papers // Jan 2010

    Measurement and Analysis of Link Quality in Wireless Networks: An Application Perspective

    Estimating the quality of wireless link is vital to optimize several protocols and applications in wireless networks. In realistic wireless networks, link quality is generally predicted by measuring received signal strength and error rates. Understanding the temporal properties of these parameters is essential for the measured values to be representative,...

    Provided By Carnegie Mellon University

  • White Papers // May 2012

    Cloud Terminal: Secure Access to Sensitive Applications From Untrusted Systems

    Current PC- and web-based applications provide insufficient security for the information they access, because vulnerabilities anywhere in a large client software stack can compromise confidentiality and integrity. The authors propose a new architecture for secure applications, Cloud Terminal, in which the only software running on the end host is a...

    Provided By Carnegie Mellon University

  • White Papers // Jun 2012

    Care: Content Aware Redundancy Elimination for Disaster Communications on Damaged Networks

    During a disaster scenario, situational awareness information, such as location, physical status and images of the surrounding area, is essential for minimizing loss of life, injury, and property damage. Today's handhelds make it easy for people to gather data from within the disaster area in many formats, including text, images...

    Provided By Carnegie Mellon University

  • White Papers // May 2011

    A Proof-Carrying File System With Revocable and Use-Once Certificates

    The authors present the design and implementation of a file system which allows authorizations dependent on revocable and use-once policy certificates. Authorizations require explicit proof objects, combining ideas from previous authorization logics and Girard's linear logic. Use-once certificates and revocations lists are maintained in a database that is consulted during...

    Provided By Carnegie Mellon University

  • White Papers // May 2011

    New Modalities for Access Control Logics: Permission, Control and Ratification

    The authors present a new modal access control logic ACL+ to specify, reason about and enforce access control policies. The logic includes new modalities for permission, control, and ratification to overcome some limits of current access control logics. They present a Hilbert-style proof system for ACL+ and a sound and...

    Provided By Carnegie Mellon University

  • White Papers // Feb 2011

    Verification of Information Flow and Access Control Policies With Dependent Types

    The authors present Relational Hoare Type Theory (RHTT), a novel language and verification system capable of expressing and verifying rich information flow and access control policies via dependent types. They show that a number of security policies which have been formalized separately in the literature can all be expressed in...

    Provided By Carnegie Mellon University

  • White Papers // Dec 2010

    On Adversary Models and Compositional Security

    The authors present a representative development in the science of security that includes a generic model of computer systems, their security properties and adversaries who actively interfere with such systems. They describe logic-based methods to reason about security properties of a system as a composition of properties of its components,...

    Provided By Carnegie Mellon University

  • White Papers // Mar 2009

    A Logic of Secure Systems and Its Application to Trusted Computing

    The authors present a logic for reasoning about properties of secure systems. The logic is built around a concurrent programming language with constructs for modeling machines with shared memory, a simple form of access control on memory, machine resets, cryptographic operations, network communication, and dynamically loading and executing unknown (and...

    Provided By Carnegie Mellon University