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TAU: Trust via Asynchronous Updates for satellite network resiliency

Summary

Satellite networks are key enablers to many applications, including world-wide sensing and communications. Unlike their terrestrial counterparts, satellites are able to provide coverage in remote and hard-to-reach areas, including areas with regional conflicts. However, they are also susceptible to multiple security threats and potential failures. In addition to commonly used security techniques, it is essential to have algorithms that assess the trustworthiness of satellites as they operate, without limiting the satellites' abilities to perform their intended tasks. In this paper we focus on trust assessment methods that analyze the behavior of satellites to detect attacks and identify failed or compromised nodes in constellation networks. In this work, we (1) present a satellite threat model and enumerate possible attacks, (2) compare several existing trust assessment models when applied to low earth orbit satellite constellations, and (3) propose Trust via Asynchronous Updates (TAU), a novel trust algorithm model that is applicable to all modern satellite constellation networks. Model TAU uses finite state machines and asynchronous updates to track node behavior. Our custom simulator evaluates the performance of our algorithm in comparison to several previously proposed trust models. We consider two well-known attacks, the kinetic and black hole attacks, and show that the proposed Model TAU accurately identifies malicious satellites, with low false positive rate, in time comparable to previously proposed trust models while achieving lower computational complexity and communication overhead.
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Summary

Satellite networks are key enablers to many applications, including world-wide sensing and communications. Unlike their terrestrial counterparts, satellites are able to provide coverage in remote and hard-to-reach areas, including areas with regional conflicts. However, they are also susceptible to multiple security threats and potential failures. In addition to commonly used...

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In-grown diamond color centers with narrow inhomogeneous spectral distributions

Summary

We characterize silicon vacancies in a bulk diamond sample grown at MIT Lincoln Laboratory. The measured narrow, inhomogeneous spectral distribution indicates that they will be useful for implementing scalable quantum networks.
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Summary

We characterize silicon vacancies in a bulk diamond sample grown at MIT Lincoln Laboratory. The measured narrow, inhomogeneous spectral distribution indicates that they will be useful for implementing scalable quantum networks.

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Impact of interconnected architectures on near-term quantum algorithms

Summary

Scaling quantum computers requires interconnected processors; however, the interconnected architecture's effect on computing performance is not well quantified. We assess the impact of architectures on algorithm performance and identify performance benefits relative to interconnect-free architectures.
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Summary

Scaling quantum computers requires interconnected processors; however, the interconnected architecture's effect on computing performance is not well quantified. We assess the impact of architectures on algorithm performance and identify performance benefits relative to interconnect-free architectures.

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It is time to standardize principles and practices for software memory safety

Summary

For many decades, endemic memory-safety vulnerabilities in software trusted computing bases (TCBs) have enabled the spread of malware and devastating targeted attacks on critical infrastructure, national-security targets, companies, and individuals around the world. During the last two years, the information-technology industry has seen increasing calls for the adoption of memory-safety technologies, frames as part of a broader initiative for Secure by Design, from government, academia, and within the industry itself. These calls are grounded in extensive evidence that memory-safety vulnerabilities have persistently made up the majority of critical security vulnerabilities for multiple decades, and have affected all mainstream software ecosystems and products--and also the growing awareness that these problems are almost entirely avoidable by using recent advances in strong and scalable memory-safety technology. In this Inside Risks column, we explore memory-safety standardization, which we argue is an essential step to promoting universal strong memory safety in government and industry, and in turn, to ensure access to more secure software for all. During the last two decades, a set of research technologies for strong memory safety--memory-safe languages, hardware and software inventory protection, formal approaches, and software compartmentalization--have reached sufficient maturity to see early deployment in security-critical use cases. However, there remains no shared, technology-neutral terminology or framework with which to specify memory-safety requirements. This is needed to enable reliable specification, design, implementation, auditing, and procurement of strongly memory-safe systems. Failure to speak in a common language makes it difficult to understand the possibilities or communicate accurately with each other, limiting perceived benefits and hence actual demand. The lack of such a framework also acts as an impediment to potential future policy interventions, and as an impediment to stating requirements to address observed market failures preventing adoption of these technologies. Standardization would also play a critical role in improving industrial best practice, another key aspect of adoption. This Inside Risks column is derived from a longer technical report published by the same authors, which includes further case studies and applications, as well as considering the potential implications of various events and interventions on potential candidate adoption timelines.
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Summary

For many decades, endemic memory-safety vulnerabilities in software trusted computing bases (TCBs) have enabled the spread of malware and devastating targeted attacks on critical infrastructure, national-security targets, companies, and individuals around the world. During the last two years, the information-technology industry has seen increasing calls for the adoption of memory-safety...

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Capacity-based analysis of physical-layer and link-layer techniques for reliable communication over free-space optical fading channels

Summary

Free-space optical communication links can experience signal power fluctuations due to channel effects such as turbulence and pointing jitter. Systems can ensure reliable, error-free communication over fading channels by using physical-layer techniques (e.g., forward error correction with codeword interleaving) and link-layer techniques (e.g., erasure coding or ARQ). In this work, Shannon capacity analysis is used to compare the fundamental performance of different coding architectures in a variety of link conditions. For systems using coherent receivers we find that, in channels with benign to moderate fade statistics, there can be a ~3 dB link budget advantage to using physical-layer interleaving instead of deferring fade mitigation to the link layer. On the other hand, in very strong fluctuations or when system robustness is paramount, it can be advantageous to use link layer codes.
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Summary

Free-space optical communication links can experience signal power fluctuations due to channel effects such as turbulence and pointing jitter. Systems can ensure reliable, error-free communication over fading channels by using physical-layer techniques (e.g., forward error correction with codeword interleaving) and link-layer techniques (e.g., erasure coding or ARQ). In this work...

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High-fidelity control of a strongly coupled electro-nuclear spin-photon interface [e-print]

Summary

Long distance quantum networking requires combining efficient spin-photon interfaces with long-lived local memories. Group-IV color centers in diamond (SiV–, GeV–, and SnV–) are promising candidates for this application, containing an electronic spin-photon interface and dopant nuclear spin memory. Recent work has demonstrated state-of-the-art performance in spin-photon coupling and spin-spin entanglement. However, coupling between the electron and nuclear spins introduces a phase kickback during optical excitation that limits the utility of the nuclear memory. Here, we propose using the large hyperfine coupling of 117SnV– to operate the device at zero magnetic field in a regime where the memory is insensitive to optical excitation. We further demonstrate ground state spin control of a 117SnV– color center integrated in a photonic integrated circuit, showing 97.8% gate fidelity and 2.5 ms coherence time for the memory spin level. This shows the viability of the zero-field protocol for high fidelity operation, and lays the groundwork for building quantum network nodes with 117SnV– devices.
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Summary

Long distance quantum networking requires combining efficient spin-photon interfaces with long-lived local memories. Group-IV color centers in diamond (SiV–, GeV–, and SnV–) are promising candidates for this application, containing an electronic spin-photon interface and dopant nuclear spin memory. Recent work has demonstrated state-of-the-art performance in spin-photon coupling and spin-spin entanglement...

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Design and performance of a 40W uplink laser transmitter for NASA's O2O laser communications mission

Summary

NASA's Orion Artemis II Optical Communications System (O2O) will provide operational laser communications between the ground and lunar orbit for the Artemis II crewed mission. In this work we describe a 40 W ground-based laser transmitter for the O2O system. The uplink transmitter operates in the optical C-band and uses an energy-efficient 32- PPM modulation format. Four spatial diversity channels are time-aligned and combined in the far field. Each channel produces up to 10 W of output power and contains both the communications signal and the 7 kHz modulated beacon signal required for acquisition. The transmitter delivers data at 10 Mbits/s and 20 Mbits/s channel rates, corresponding to the 250 MHz and 500 MHz slot rates respectively.
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Summary

NASA's Orion Artemis II Optical Communications System (O2O) will provide operational laser communications between the ground and lunar orbit for the Artemis II crewed mission. In this work we describe a 40 W ground-based laser transmitter for the O2O system. The uplink transmitter operates in the optical C-band and uses...

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On-orbit pointing performance of the Modular Agile Scalable Optical Terminal (MAScOT) for the ILLUMA-T mission

Summary

The Integrated LCRD LEO User Modem and Amplifier Terminal (ILLUMA-T) payload was the first space-based user terminal to demonstrate successful two-way optical communications with a ground terminal via NASA's Laser Communications Relay Demonstration (LCRD). In order to acquire the link, the ILLUMA-T optical module open loop points a wide beacon at the LCRD acquisition sensor. The initial pointing of the beacon is based on real-time ISS position and attitude information and precalculated LCRD ephemeris. This paper examines the on-orbit pointing performance of ILLUMA-T during the mission.
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Summary

The Integrated LCRD LEO User Modem and Amplifier Terminal (ILLUMA-T) payload was the first space-based user terminal to demonstrate successful two-way optical communications with a ground terminal via NASA's Laser Communications Relay Demonstration (LCRD). In order to acquire the link, the ILLUMA-T optical module open loop points a wide beacon...

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Software vulnerability detection using LLM: does additional information help?

Summary

Unlike conventional machine learning (ML) or deep learning (DL) methods, Large Language Models (LLM) possess the ability to tackle complex tasks through intricate chains of reasoning, a facet often overlooked in existing work on vulnerability detection. Nevertheless, these models have demonstrated variable performance when presented with different prompts (inputs), motivating a surge of research into prompt engineering – the process of optimizing prompts to enhance their performance. This paper studies different prompt settings (zero-shot and few-shot) when using LLMs for software vulnerability detection. Our exploration involves harnessing the power of both natural language (NL) unimodal and NL-PL (programming language) bimodal models within the prompt engineering process. Experimental results indicate that LLM, when provided only with source code or zero-shot prompts, tends to classify most code snippets as vulnerable, resulting in unacceptably high recall. These findings suggest that, despite their advanced capabilities, LLMs may not inherently possess the knowledge for vulnerability detection tasks. However, fewshot learning benefits from additional domain-specific knowledge, offering a promising direction for future research in optimizing LLMs for vulnerability detection.
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Summary

Unlike conventional machine learning (ML) or deep learning (DL) methods, Large Language Models (LLM) possess the ability to tackle complex tasks through intricate chains of reasoning, a facet often overlooked in existing work on vulnerability detection. Nevertheless, these models have demonstrated variable performance when presented with different prompts (inputs), motivating...

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Exploiting temporal vulnerabilities for unauthorized access in intent-based networking

Published in:
ACM Conf. on Computer and Communications Security, CCS '24, 14-18 October 2024.

Summary

Intent-based networking (IBN) enables network administrators to express high-level goals and network policies without needing to specify low-level forwarding configurations, topologies, or protocols. Administrators can define intents that capture the overall behavior they want from the network, and an IBN controller compiles such intents into low-level configurations that get installed in the network and implement the desired behavior. We discovered that current IBN specifications and implementations do not specify that flow rule installation orderings should be enforced, which leads to temporal vulnerabilities where, for a limited time, attackers can exploit indeterminate connectivity behavior to gain unauthorized network access. In this paper, we analyze the causes of such temporal vulnerabilities and their security impacts with a representative case study via the ONOS IBN implementation.We devise the Phantom Link attack and demonstrate a working exploit to highlight the security impacts. To defend against such attacks, we propose Spotlight, a detection method that can alert a system administrator of risky intent updates prone to exploitable temporal vulnerabilities. Spotlight is effective in identifying risky updates using realistic network topologies and policies. We show that Spotlight can detect risky updates in a mean time of 0.65 seconds for topologies of over 1,300 nodes.
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Summary

Intent-based networking (IBN) enables network administrators to express high-level goals and network policies without needing to specify low-level forwarding configurations, topologies, or protocols. Administrators can define intents that capture the overall behavior they want from the network, and an IBN controller compiles such intents into low-level configurations that get installed...

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