Open-Source DTN Framework Enables Reliable ISS Communication

Delay and Disruption Tolerant Networks are essential for space communications where constant connectivity is impossible. Researchers Krit Grover and Marcelo Ponce have released an open-source, full-stack implementation of the Bundle protocol specifically designed for International Space Station communication. The framework, presented at the 29th International Symposium on Real-Time Distributed Computing (ISORC 2026), covers the complete DTN stack—from bundle fragmentation and reassembly to priority-based queuing and custody transfer with ACK/NAK mechanisms. It also includes automatic retransmission to handle the extreme latencies of orbital links.

On the security front, the system supports Bundle Authentication Block (BAB), Payload Integrity Block (PIB), and Payload Confidentiality Block (PCB) using HMAC-SHA256 and AES-256-CBC encryption. This ensures both data integrity and confidentiality over challenged links. A modern responsive web interface provides interactive control, making the framework useful not only for production emulation but also as an educational tool for computer networking students. By offering a freely available, realistic DTN emulator, the team aims to accelerate research in resilient space communication protocols—a critical need as satellite constellations and deep-space missions multiply.