Cybersecurity meets Space Radiation Securing Satellite Communications with AES-GCM-256: Challenges and Solutions

Satellite communications are the backbone of modern connectivity, supporting everything from global navigation and weather forecasting to broadband internet and defence operations. Yet these systems face a dual challenge: rising cyber threats and constant exposure to space radiation. Both can compromise data integrity, disrupt encryption, and jeopardize mission-critical reliability. This article explores the risks and highlights how integrated, radiation-hardened cryptographic solutions—such as Microchip’s AES-GCM-256 platform—are redefining secure communications in orbit.

In an era where global connectivity, defence operations and critical infrastructure increasingly rely on satellite communications, the integrity and security of data transmitted through space has never been more vital. From GPS navigation and weather forecasting to military reconnaissance and broadband internet, satellites form the backbone of modern communication systems. However, as indispensable as these systems are, they face a unique and formidable set of challenges—chief among them, the dual threat of cyber vulnerabilities and space radiation.

The Growing Importance—and Vulnerability—of Satellite Communications

Satellite communications are inherently exposed. Unlike terrestrial networks, which can be physically secured and monitored, satellites operate in the vast openness of space, transmitting signals across thousands of miles. This makes them susceptible to a wide range of threats:

•  Eavesdropping and interception: Adversaries can attempt to intercept satellite signals to gain unauthorized access to sensitive data.
• Data tampering and spoofing: Malicious actors may try to alter or forge data in transit, undermining the trustworthiness of the communication.
• Denial-of-service attacks: Jamming or flooding satellite channels can disrupt critical services, from navigation to emergency response.
• These threats are not hypothetical. Incidents of satellite signal jamming and spoofing have been documented in both civilian and military contexts. As geopolitical tensions rise and the commercial space sector expands, the attack surface for satellite communications continues to grow.

The Hidden Threat: Radiation-Induced Errors

While cybersecurity threats are well-known, a less visible but equally dangerous challenge lies in the physical environment of space itself. Satellites operate in a high-radiation environment where they are constantly bombarded by cosmic rays, solar particles and trapped radiation belts. These high-energy particles can cause Single Event Effects (SEEs), which are disruptions in electronic circuits caused by a single ionizing particle.

One of the most common SEEs is the Single Event Upset (SEU), where a charged particle strikes a semiconductor device and flips a bit in memory or logic. In the context of satellite communications, this can lead to:

• Corrupted data packets: A single flipped bit can render a message unreadable or incorrect.
• Loss of encryption integrity: If a bit flip occurs in an encryption key or authentication tag, it can invalidate the entire cryptographic process.
• System instability: Repeated SEUs can accumulate and cause broader system malfunctions or failures.

These radiation-induced errors are particularly insidious because they are random, difficult to predict, and can mimic the effects of cyberattacks or hardware faults. Traditional error detection and correction methods, while helpful, are not always sufficient—especially when data integrity and security are paramount.

The Challenge of Balancing Security, Performance and Reliability

To address these threats, satellite systems must implement robust encryption and authentication mechanisms. The Advanced Encryption Standard (AES) is widely used for this purpose, offering strong protection against unauthorized access. However, not all encryption modes are created equal.

In high-performance, real-time communication systems like those used in satellites, encryption must be:

• Fast and efficient: Latency and throughput are critical in satellite links.
• Authenticated: Encryption alone is not enough; data must also be verified for integrity.
• Resilient to radiation: Cryptographic operations must tolerate SEUs without compromising security.

This is where traditional encryption schemes often fall short. Many do not provide built-in authentication, requiring additional mechanisms to verify data integrity. Others are not optimized for the constrained power and processing environments of spaceborne systems. And few are designed with radiation resilience in mind.

The Hardware Gap: Limitations of Conventional Platforms

Even the best cryptographic algorithms are only as effective as the hardware they run on. In space applications, hardware must meet stringent requirements:

• Radiation tolerance: Devices must withstand SEUs and other radiation effects without data loss or corruption.
• Low power consumption: Satellites have limited power budgets, especially in small form-factor platforms like CubeSats.
• Secure key storage: Cryptographic keys must be protected from both physical and logical attacks.
• High-speed I/O: To support modern data rates, hardware must offer fast, reliable interfaces.

Conventional FPGAs and processors often struggle to meet these demands. Volatile configuration memory is vulnerable to SEUs. External key storage can be a security risk. And general-purpose processors may lack the performance needed for real-time encryption and authentication.

The Need for an Integrated, Radiation-Hardened Security Solution

Given these challenges, the satellite industry needs a new approach—one that integrates robust cryptographic capabilities with radiation-hardened hardware and efficient system design. The ideal solution must:

• Combine encryption and authentication in a single, efficient algorithm.
• Detect and respond to SEUs in real time, ensuring data integrity even in the presence of radiation.
• Leverage secure, non-volatile memory for key storage and initialization vectors.
• Leverage secure, non-volatile memory for key storage and initialization vectors. Offload cryptographic operations to dedicated hardware to reduce CPU load and power consumption.
• Provide a scalable platform that can be tailored to different mission profiles and performance requirements.

Microchip addressed this problem with a solution that integrates Advanced Encryption Standard - Galois/Counter Mode (AES-GCM) encryption with authentication, radiation-tolerant FPGA fabric, and a dedicated crypto coprocessor—all within a secure, low-power platform.

Summary of the AES-GCM-256 Solution for Secure Satellite Communications

To address the multifaceted challenges of secure and reliable satellite communications, Microchip presents a robust solution built around the AES-GCM-256 encryption algorithm, implemented on Microchip’s PolarFire^® FPGA and RT PolarFire FPGA and SoC platforms. This solution is designed to ensure both data confidentiality and integrity while withstanding the harsh radiation environment of space.

Key highlights include:

• AES-GCM-256 integration: The solution leverages AES-GCM, which combines encryption and authentication in a single, efficient algorithm. This dual capability is critical for detecting both malicious tampering and radiation-induced bit flips.
• Radiation-tolerant hardware: PolarFire FPGAs feature configuration logic that is immune to Single Event Upsets (SEUs), along with Single Error Correction, Double Error Detection (SECDED)-protected memory blocks and secure non-volatile memory (sNVM), making them ideal for space applications.
• Dedicated crypto coprocessor: The Athena TeraFire® EXP5200B Crypto Coprocessor offloads cryptographic operations from the main processor, improving performance and reducing power consumption. It also includes a true random number generator for secure IV generation.
• Secure key management: Encryption keys are stored in on-chip sNVM, protected by AES-SIV encryption, ensuring secure data at rest. The system supports secure provisioning and runtime key management.
• End-to-end message protection: Messages are encrypted, authenticated and stored in SEU-immune buffers before transmission. On the receiving end, the same architecture verifies message integrity and authenticity, with failed authentications triggering retransmission requests.

• Demonstration design: A working demo on the PolarFire MPF300TS device showcases the full encryption-decryption cycle using test vectors, with support for automated testing via TeraTerm macro scripts.

Microchip’s PolarFire FPGA provides a robust and secure platform for implementing advanced cryptographic solutions, such as the AES-GCM-256 encryption algorithm. In this architecture, a soft RISC-V CPU (Mi-V™) orchestrates system operations, with its application code stored and executed from high-speed LSRAM memory blocks within the FPGA fabric. The Mi-V processor interfaces with several key peripherals to deliver a comprehensive encryption solution.

The Athena TeraFire crypto coprocessor is leveraged for hardware-accelerated AES-GCM encryption and random number generation, ensuring both performance and security. Encrypted messages are temporarily stored in a dedicated LSRAM message buffer, while System Services provide a secure interface to the sNVM block for storing and accessing AES cryptographic keys. Additionally, a UART interface enables user interaction, allowing payload data and parameters to be sourced for demonstration purposes. This tightly integrated design highlights the flexibility and security of the PolarFire FPGA platform for modern cryptographic applications.

The integrated approach not only secures satellite communications against cyber threats but also provides a resilient defence against the unpredictable effects of space radiation. It exemplifies how modern cryptographic techniques, when paired with radiation-hardened hardware, can deliver trustworthy and high-performance communication systems for space missions.

Tim Morin is a technical fellow for Microchip’s FPGA business unit.