scholarly journals TLB-pilot: Mitigating TLB Contention Attack on GPUs with Microarchitecture-Aware Scheduling

2022 ◽  
Vol 19 (1) ◽  
pp. 1-23
Author(s):  
Bang Di ◽  
Daokun Hu ◽  
Zhen Xie ◽  
Jianhua Sun ◽  
Hao Chen ◽  
...  
Keyword(s):  
State Of The Art ◽  
Denial Of Service ◽  
System Throughput ◽  
Resource Requirement ◽  
Application Security ◽  
Translation Lookaside Buffer ◽  
Load Imbalance ◽  
High System ◽  
The Common ◽  
Software And Hardware

Co-running GPU kernels on a single GPU can provide high system throughput and improve hardware utilization, but this raises concerns on application security. We reveal that translation lookaside buffer (TLB) attack, one of the common attacks on CPU, can happen on GPU when multiple GPU kernels co-run. We investigate conditions or principles under which a TLB attack can take effect, including the awareness of GPU TLB microarchitecture, being lightweight, and bypassing existing software and hardware mechanisms. This TLB-based attack can be leveraged to conduct Denial-of-Service (or Degradation-of-Service) attacks. Furthermore, we propose a solution to mitigate TLB attacks. In particular, based on the microarchitecture properties of GPU, we introduce a software-based system, TLB-pilot, that binds thread blocks of different kernels to different groups of streaming multiprocessors by considering hardware isolation of last-level TLBs and the application’s resource requirement. TLB-pilot employs lightweight online profiling to collect kernel information before kernel launches. By coordinating software- and hardware-based scheduling and employing a kernel splitting scheme to reduce load imbalance, TLB-pilot effectively mitigates TLB attacks. The result shows that when under TLB attack, TLB-pilot mitigates the attack and provides on average 56.2% and 60.6% improvement in average normalized turnaround times and overall system throughput, respectively, compared to the traditional Multi-Process Service based co-running solution. When under TLB attack, TLB-pilot also provides up to 47.3% and 64.3% improvement (41% and 42.9% on average) in average normalized turnaround times and overall system throughput, respectively, compared to a state-of-the-art co-running solution for efficiently scheduling of thread blocks.

SCAFFY

2021 ◽  
Vol 15 (3) ◽  
pp. 106-128
Author(s):  
Muraleedharan N. ◽  
Janet B.
Keyword(s):  
Critical Infrastructure ◽  
State Of The Art ◽  
Denial Of Service ◽  
Classification Performance ◽  
Dos Attack ◽  
Dos Attacks ◽  
Flow Parameters ◽  
Machine Learning Model ◽  
The Common ◽  
Catastrophic Impact

Denial of service (DoS) attack is one of the common threats to the availability of critical infrastructure and services. As more and more services are online enabled, the attack on the availability of these services may have a catastrophic impact on our day-to-day lives. Unlike the traditional volumetric DoS, the slow DoS attacks use legitimate connections with lesser bandwidth. Hence, it is difficult to detect slow DoS by monitoring bandwidth usage and traffic volume. In this paper, a novel machine learning model called ‘SCAFFY' to classify slow DoS on HTTP traffic using flow level parameters is explained. SCAFFY uses a multistage approach for the feature section and classification. Comparison of the classification performance of decision tree, random forest, XGBoost, and KNN algorithms are carried out using the flow parameters derived from the CICIDS2017 and SUEE datasets. A comparison of the result obtained from SCAFFY with two recent works available in the literature shows that the SCAFFY model outperforms the state-of-the-art approaches in classification accuracy.

Caged-electron States and Split-electron States in Endohedral Alkali C60

2021 ◽  
Author(s):  
yifan yang ◽  
Lorenz S Cederbaum
Keyword(s):  
State Of The Art ◽  
Electronic States ◽  
Electron States ◽  
The Common ◽  
High Level

The low-lying electronic states of neutral X@C60(X=Li, Na, K, Rb) have been computed and analyzed by employing state-of-the-art high level many-electron methods. Apart from the common charge-separated states, well known...

Scalable mining of maximal quasi-cliques

2020 ◽  
Vol 14 (4) ◽  
pp. 573-585
Author(s):  
Guimu Guo ◽  
Da Yan ◽  
M. Tamer Özsu ◽  
Zhe Jiang ◽  
Jalal Khalil
Keyword(s):  
Graph Mining ◽  
State Of The Art ◽  
Minimum Degree ◽  
The Other ◽  
Dense Subgraph ◽  
Load Imbalance ◽  
Subgraph Mining ◽  
Execution Engine ◽  
Clique Algorithm ◽  
Dense Subgraph Mining

Given a user-specified minimum degree threshold γ , a γ -quasiclique is a subgraph g = (V g , E g ) where each vertex ν ∈ V g connects to at least γ fraction of the other vertices (i.e., ⌈ γ · (| V g |- 1)⌉ vertices) in g. Quasi-clique is one of the most natural definitions for dense structures useful in finding communities in social networks and discovering significant biomolecule structures and pathways. However, mining maximal quasi-cliques is notoriously expensive. In this paper, we design parallel algorithms for mining maximal quasi-cliques on G-thinker, a distributed graph mining framework that decomposes mining into compute-intensive tasks to fully utilize CPU cores. We found that directly using G-thinker results in the straggler problem due to (i) the drastic load imbalance among different tasks and (ii) the difficulty of predicting the task running time. We address these challenges by redesigning G-thinker's execution engine to prioritize long-running tasks for execution, and by utilizing a novel timeout strategy to effectively decompose long-running tasks to improve load balancing. While this system redesign applies to many other expensive dense subgraph mining problems, this paper verifies the idea by adapting the state-of-the-art quasi-clique algorithm, Quick, to our redesigned G-thinker. Extensive experiments verify that our new solution scales well with the number of CPU cores, achieving 201× runtime speedup when mining a graph with 3.77M vertices and 16.5M edges in a 16-node cluster.

scholarly journals DCPNet: A Densely Connected Pyramid Network for Monocular Depth Estimation

Sensors ◽  
2021 ◽  
Vol 21 (20) ◽  
pp. 6780
Author(s):  
Zhitong Lai ◽  
Rui Tian ◽  
Zhiguo Wu ◽  
Nannan Ding ◽  
Linjian Sun ◽  
...  
Keyword(s):  
Multiple Scales ◽  
Feature Fusion ◽  
State Of The Art ◽  
Depth Estimation ◽  
Multi Scale ◽  
Pyramid Structure ◽  
Benchmark Datasets ◽  
The Common ◽  
Monocular Depth ◽  
Multiple Stages

Pyramid architecture is a useful strategy to fuse multi-scale features in deep monocular depth estimation approaches. However, most pyramid networks fuse features only within the adjacent stages in a pyramid structure. To take full advantage of the pyramid structure, inspired by the success of DenseNet, this paper presents DCPNet, a densely connected pyramid network that fuses multi-scale features from multiple stages of the pyramid structure. DCPNet not only performs feature fusion between the adjacent stages, but also non-adjacent stages. To fuse these features, we design a simple and effective dense connection module (DCM). In addition, we offer a new consideration of the common upscale operation in our approach. We believe DCPNet offers a more efficient way to fuse features from multiple scales in a pyramid-like network. We perform extensive experiments using both outdoor and indoor benchmark datasets (i.e., the KITTI and the NYU Depth V2 datasets) and DCPNet achieves the state-of-the-art results.

scholarly journals Peningkatan Keamanan Router Mikrotik Terhadap Serangan Denial of Service (DoS)

2020 ◽  
pp. 115-123
Author(s):  
Budi Jaya ◽  
Y Yuhandri ◽  
S Sumijan
Keyword(s):  
Denial Of Service ◽  
Digital Evidence ◽  
Dos Attack ◽  
Dos Attacks ◽  
Research Results ◽  
Security Enhancement ◽  
Software And Hardware ◽  
Operational Activities ◽  
Network Router ◽  
Live Forensics

Denial of Service (DoS) attacks are one of the most common attacks on website, networks, routers and servers, including on router mikrotik. A DoS attack aims to render a network router unable to service requests from authorized users. The result will disrupt the operational activities of the organization and cause material and non-material losses. In this study, a simulation and analysis of DoS attacks using the Live Forensics method were carried out and the router security enhancement from rectangular software and hardware. From the research results obtained digital evidence of DoS attacks in the form of IP addresses and attacker activity logs. In addition, the increase in router security in terms of software by using Firewall Filter and Firewall Raw has proven effective in preventing attacks. While improving router security in terms of hardware by setting a reset button on the router and firewall devices is also very necessary so that the router can avoid physical attacks by irresponsible persons

scholarly journals Analyze COVID-19 CT images based on evolutionary algorithm with dynamic searching space

2021 ◽  
Author(s):  
Yunhong Gong ◽  
Yanan Sun ◽  
Dezhong Peng ◽  
Peng Chen ◽  
Zhongtai Yan ◽  
...  
Keyword(s):  
Common Sense ◽  
Expert Knowledge ◽  
State Of The Art ◽  
Data Set ◽  
The Past ◽  
Computed Tomography Images ◽  
Intensive Use ◽  
Hospital Resources ◽  
The Common ◽  
Ct Data

AbstractThe COVID-19 pandemic has caused a global alarm. With the advances in artificial intelligence, the COVID-19 testing capabilities have been greatly expanded, and hospital resources are significantly alleviated. Over the past years, computer vision researches have focused on convolutional neural networks (CNNs), which can significantly improve image analysis ability. However, CNN architectures are usually manually designed with rich expertise that is scarce in practice. Evolutionary algorithms (EAs) can automatically search for the proper CNN architectures and voluntarily optimize the related hyperparameters. The networks searched by EAs can be used to effectively process COVID-19 computed tomography images without expert knowledge and manual setup. In this paper, we propose a novel EA-based algorithm with a dynamic searching space to design the optimal CNN architectures for diagnosing COVID-19 before the pathogenic test. The experiments are performed on the COVID-CT data set against a series of state-of-the-art CNN models. The experiments demonstrate that the architecture searched by the proposed EA-based algorithm achieves the best performance yet without any preprocessing operations. Furthermore, we found through experimentation that the intensive use of batch normalization may deteriorate the performance. This contrasts with the common sense approach of manually designing CNN architectures and will help the related experts in handcrafting CNN models to achieve the best performance without any preprocessing operations

scholarly journals Towards Effective Detection of Recent DDoS Attacks: A Deep Learning Approach

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Ivandro Ortet Lopes ◽  
Deqing Zou ◽  
Francis A Ruambo ◽  
Saeed Akbar ◽  
Bin Yuan
Keyword(s):  
Deep Learning ◽  
Intrusion Detection System ◽  
State Of The Art ◽  
Detection System ◽  
Denial Of Service ◽  
Model Performance ◽  
Distributed Denial Of Service ◽  
Ddos Attacks ◽  
Validation Metrics ◽  
High Processing

Distributed Denial of Service (DDoS) is a predominant threat to the availability of online services due to their size and frequency. However, developing an effective security mechanism to protect a network from this threat is a big challenge because DDoS uses various attack approaches coupled with several possible combinations. Furthermore, most of the existing deep learning- (DL-) based models pose a high processing overhead or may not perform well to detect the recently reported DDoS attacks as these models use outdated datasets for training and evaluation. To address the issues mentioned earlier, we propose CyDDoS, an integrated intrusion detection system (IDS) framework, which combines an ensemble of feature engineering algorithms with the deep neural network. The ensemble feature selection is based on five machine learning classifiers used to identify and extract the most relevant features used by the predictive model. This approach improves the model performance by processing only a subset of relevant features while reducing the computation requirement. We evaluate the model performance based on CICDDoS2019, a modern and realistic dataset consisting of normal and DDoS attack traffic. The evaluation considers different validation metrics such as accuracy, precision, F1-Score, and recall to argue the effectiveness of the proposed framework against state-of-the-art IDSs.

scholarly journals Multiresolution dendritic cell algorithm for network anomaly detection

2021 ◽  
Vol 7 ◽  
pp. e749
Author(s):  
David Limon-Cantu ◽  
Vicente Alarcon-Aquino
Keyword(s):  
Information Systems ◽  
Dendritic Cell ◽  
Anomaly Detection ◽  
State Of The Art ◽  
Denial Of Service ◽  
Series Data ◽  
Time Frequency ◽  
Computer Services ◽  
Dendritic Cell Algorithm ◽  
Network Anomaly Detection

Anomaly detection in computer networks is a complex task that requires the distinction of normality and anomaly. Network attack detection in information systems is a constant challenge in computer security research, as information systems provide essential services for enterprises and individuals. The consequences of these attacks could be the access, disclosure, or modification of information, as well as denial of computer services and resources. Intrusion Detection Systems (IDS) are developed as solutions to detect anomalous behavior, such as denial of service, and backdoors. The proposed model was inspired by the behavior of dendritic cells and their interactions with the human immune system, known as Dendritic Cell Algorithm (DCA), and combines the use of Multiresolution Analysis (MRA) Maximal Overlap Discrete Wavelet Transform (MODWT), as well as the segmented deterministic DCA approach (S-dDCA). The proposed approach is a binary classifier that aims to analyze a time-frequency representation of time-series data obtained from high-level network features, in order to classify data as normal or anomalous. The MODWT was used to extract the approximations of two input signal categories at different levels of decomposition, and are used as processing elements for the multi resolution DCA. The model was evaluated using the NSL-KDD, UNSW-NB15, CIC-IDS2017 and CSE-CIC-IDS2018 datasets, containing contemporary network traffic and attacks. The proposed MRA S-dDCA model achieved an accuracy of 97.37%, 99.97%, 99.56%, and 99.75% for the tested datasets, respectively. Comparisons with the DCA and state-of-the-art approaches for network anomaly detection are presented. The proposed approach was able to surpass state-of-the-art approaches with UNSW-NB15 and CSECIC-IDS2018 datasets, whereas the results obtained with the NSL-KDD and CIC-IDS2017 datasets are competitive with machine learning approaches.

Open Judiciary Worldwide

2020 ◽  
pp. 1207-1221
Author(s):  
Carlos E. Jiménez-Gómez
Keyword(s):  
Exploratory Study ◽  
Success Factors ◽  
State Of The Art ◽  
Common Law ◽  
The State ◽  
Preliminary Results ◽  
Critical Success ◽  
Learning Practices ◽  
The Common ◽  
Research Questions

Despite its origins, openness in the judiciary has expanded beyond transparency and, therefore, beyond the common law open justice principle. Several initiatives worldwide are echoing this trend and a new term, open judiciary, is arising as a way to address openness in the justice field. This chapter gives an overview of open judiciary initiatives worldwide, focusing on some of the most successful, in order to identify drivers of adoption, critical success factors, and preliminary results. The research is embedded in a broader exploratory study on the state of the art of open judiciary. The chapter is addressed to answer two of the research questions: What are some learning practices that can be identified worldwide in relation to openness in the judiciary? What are some of the most important lessons that can be learnt from these practices?

scholarly journals What Can Be Accomplished with the State of the Art in Information Extraction? A Personal View

2018 ◽  
Vol 44 (4) ◽  
pp. 651-658
Author(s):  
Ralph Weischedel ◽  
Elizabeth Boschee
Keyword(s):  
Information Extraction ◽  
State Of The Art ◽  
The State ◽  
Personal View ◽  
Common Features ◽  
Research Challenges ◽  
The Common

Though information extraction (IE) research has more than a 25-year history, F1 scores remain low. Thus, one could question continued investment in IE research. In this article, we present three applications where information extraction of entities, relations, and/or events has been used, and note the common features that seem to have led to success. We also identify key research challenges whose solution seems essential for broader successes. Because a few practical deployments already exist and because breakthroughs on particular challenges would greatly broaden the technology’s deployment, further R&D investments are justified.

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