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Network-on-chip facilitates glueless interconnection of various on-chip components in the forthcoming system-on-chips. As in the case of any new technology, security is a major concern in network-on-chip (NoC) design too. In this work, we explore a covert threat model for multiprocessor system-on-chips (MPSoCs) stemming from the use of malicious third-party network-on-chips (NoCs). We illustrate that a rogue NoC (rNoC) can selectively disrupt the perceived availability of on-chip resources, thereby causing large performance bottlenecks for the applications running on the MPSoC platform. Further, to counter the threat posed by rNoC, we propose a runtime latency auditor that enables an MPSoC integrator to monitor the trustworthiness of the deployed NoC throughout the chip lifetime. We also discuss measures that can be taken to minimize the impact of a rNoC, once it is detected. Our comprehensive cross-layer analysis of our novel detection technique indicates modest overheads of 12.73% in area, 9.844% in power, and 5.4% in terms of network latency.

With aggressive technology scaling, the complexity of the global routing problem is poised to grow rapidly. Solving such a large computational problem demands a high-throughput hardware platform such as modern graphics processing units (GPUs). In this paper, we explore a hybrid GPU-CPU high-throughput computing environment as a scalable alternative to the traditional CPU-based router. We introduce net-level concurrency (NLC), which is a novel parallel model for router algorithms and aims to exploit concurrency at the level of individual nets. To efficiently uncover NLC, we design a scheduler to create groups of nets that can be routed in parallel. At its core, our scheduler employs a novel algorithm to dynamically analyze data dependencies between multiple nets. We believe such an algorithm can lay the foundation for uncovering data-level parallelism in routing, which is a necessary requirement for employing high-throughput hardware. Detailed simulation results show an average of 4× speedup over NTHU-Route 2.0 with negligible loss in solution quality. To the best of our knowledge, this is the first work on utilizing GPUs for global routing.

In this paper, we propose a covert threat model for MPSoCs designed using 3rd party Network-on-Chips (NoC). We illustrate that a malicious NoC can disrupt the availability of on-chip resources, thereby causing large performance bottlenecks for the software running on the MPSoC platform. We then propose a runtime latency auditor that enables an MPSoC integrator to monitor the trustworthiness of the deployed NoC throughout the chip lifetime. For the proposed technique, our comprehensive cross-layer analysis indicates modest overheads of 12.73% in area, 9.844% in power and 5.4% in terms of network latency.

Aggressive technology scaling exacerbates the problem of voltage emergencies in emerging MPSoC systems. Network-on-Chips, the de-facto standard for connecting on-chip components in forthcoming devices play a central role in providing robust and reliable communication. In this work, we propose DrNoC (droop resilient network-on-chip)-two microarchitectural techniques to mitigate voltage emergency-induced timing errors in NoCs and preserve error-free communication throughout the network. DrNoC employs frequency downscaling and a pipeline error-recovery mechanism to reclaim corrupted flits in the router. Compared to the recently proposed NSFTR fault-tolerant technique, DrNoC offers a 27% improvement in energy-delay efficiency.

Network-On-Chips (NoCs) have become the standard communication platform for future massively parallel systems due to their performance, flexibility and scalability advantages. However, reliability issues brought about by scaling in the sub-20nm era threaten to undermine the benefits offered by NoCs. In this paper, we showthat QoS policies exacerbate the reliability profile of an exascale system. To mitigate this imposing challenge, we propose Dynamic Wearout Resilient Routing (DWRR) algorithms in QoS-enabled exascale NoCs. Our proposal includes two novel DWRR algorithms enabled by a critical-path monitor and a broadcast-based routing configuration. Using PARSEC benchmarks, our best algorithm improves QoS and long-term sustainability (Mean Time To Failure) of the system by an average of 16% and 25% compared to a state-of-the-art fault tolerant technique, respectively. Copyright 2014 ACM.

In this paper, we uncover a novel and imminent threat to an emerging computing paradigm: MPSoCs built with 3rd party IP NoCs. We demonstrate that a compromised NoC (C-NoC) can enable a range of security attacks with an accomplice software component. To counteract these threats, we propose Fort-NoCs, a series of techniques that work together to provide protection from a C-NoC in an MPSoC. Fort-NoCs's foolproof protection disables covert backdoor activation, and reduces the chance of a successful side-channel attack by "clouding" the information obtained by an attacker. Compared to recently proposed techniques, Fort-NoCs offers a substantially better protection with lower overheads. Copyright 2014 ACM.

Early prediction of an upcoming timing violation presents a tremendous opportunity to mask the performance overhead of tolerating these faults. In this paper, we explore several techniques for optimizing instruction scheduling in an Out-of-Order pipeline, exploiting this new perspective in robust system design. Compared to recently proposed stall based techniques for tolerating predictabletiming violations, we demonstrate a massive reduction in performance overhead, while supporting correct execution in faulty environments (64-97% across different benchmarks). Copyright © 2013 ACM.