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Convolutional Neural Networks (CNNs) are widely used in various domains, including image recognition, medical diagnosis and autonomous driving. Recent advances in dataflow-based CNN accelerators have enabled CNN inference in resource-constrained edge devices. These dataflow accelerators utilize inherent data reuse of convolution layers to process CNN models efficiently. Concealing the architecture of CNN models is critical for privacy and security. This article evaluates memory-based side-channel information to recover CNN architectures from dataflow-based CNN inference accelerators. The proposed attack exploits spatial and temporal data reuse of the dataflow mapping on CNN accelerators and architectural hints to recover the structure of CNN models. Experimental results demonstrate that our proposed side-channel attack can recover the structures of popular CNN models, namely, Lenet, Alexnet, VGGnet16, and YOLOv2. 

Network-on-chip (NoC) is widely used to facilitate communication between components in sophisticated system-on-chip (SoC) designs. Security of the on-chip communication is crucial because exploiting any vulnerability in shared NoC would be a goldmine for an attacker that puts the entire computing infrastructure at risk. We investigate the security strength of existing anonymous routing protocols in NoC architectures, making two pivotal contributions. Firstly, we develop and perform a machine learning (ML)-based flow correlation attack on existing anonymous routing techniques in NoC systems, revealing that they provide only packet-level anonymity. Secondly, we propose a novel, lightweight anonymous routing protocol featuring outbound traffic tunneling and traffic obfuscation. This protocol is designed to provide robust defense against ML-based flow correlation attacks, ensuring both packet-level and flow-level anonymity. Experimental evaluation using both real and synthetic traffic demonstrates that our proposed attack successfully deanonymizes state-of-the-art anonymous routing in NoC architectures with high accuracy (up to 99%) for diverse traffic patterns. It also reveals that our lightweight anonymous routing protocol can defend against ML-based attacks with minor hardware and performance overhead. 

Advances in chip manufacturing technologies have enabled computer architects to utilize System-on-Chip (SoC) to integrate the intellectual property cores as well as other components. Network-on-Chip (NoC) is widely used to fulfill communication requirements in SoC architectures. Securing NoC is vital for designing trustworthy SoCs. Eavesdropping attacks can exploit NoC vulnerabilities to extract secret information. In this paper, we propose a machine learning based detection of eavesdropping attacks. Our machine learning models are trained offline and have been used for runtime detection with a collective decision making strategy. Experimental results demonstrate that our approach can provide high accuracy with minimal overhead. 

Network-on-Chip (NoC) fulfills the communication requirements of modern System-on-Chip (SoC) architectures. Due to the resource-constrained nature of NoC-based SoCs, it is a major challenge to secure on-chip communication against eavesdropping attacks using traditional encryption methods. In this paper, we propose a lightweight encryption technique using chaffing and winnowing (C&W) with all-or-nothing transform (AONT) that benefits from the unique NoC traffic characteristics. Our experimental results demonstrate that our proposed encryption technique provides the required security with significantly less area and energy overhead compared to the state-of-the-art approaches. 

State-of-the-art System-on-Chip (SoC) designs consist of many Intellectual Property (IP) cores that interact using a Network-on-Chip (NoC) architecture. SoC designers increasingly rely on global supply chains for obtaining third-party IPs. In addition to inherent vulnerabilities associated with utilizing third-party IPs, NoC based SoCs enable attackers to exploit the distributed nature of NoC and its connectivity with various IPs to launch a plethora of attacks. Specifically, Denial-of-Service (DoS) attacks pose a serious threat in degrading the SoC performance by flooding the NoC with unnecessary packets. In this paper, we present a machine learning-based runtime monitoring mechanism to detect DoS attacks. The models are statically trained and used for runtime attack detection leading to minimum runtime performance overhead. Our approach is capable of detecting DoS attacks with high accuracy, even in the presence of unpredictable NoC traffic patterns caused by various application mappings. We extensively explore machine learning models and features to provide a comprehensive study on how to use machine learning for DoS attack detection in NoC-based SoCs. 

Multithreaded applications are capable of exploiting the full potential of many-core systems. However, network-on-chip (NoC)-based intercore communication in many-core systems is responsible for 60%-75% of the miss latency experienced by multithreaded applications. Delay in the arrival of critical data at the requesting core severely hampers performance. This brief presents some interesting insights about how critical data are requested from the memory by multithreaded applications. Then it investigates the cause of delay in NoC and how it affects the performance. Finally, this brief shows how NoC-aware memory access optimizations can significantly improve performance. Our experimental evaluation considers early restart memory access optimization and demonstrates that by exploiting available NoC resources, critical data can be prioritized to reduce miss penalty by 11% and improve overall system performance by 9%.