IP-based networking over HF radio has historically been challenging due to high latencies, narrow bandwidths, and variable link conditions. Most IP protocols expect immediate feedback and uninterrupted service. These are characteristics fundamentally absent from traditional HF radios.
With the introduction of Cognitive Networked HF (CNHF) technology, real-time IP communication over HF is now a proven reality.
The system supports UDP tunneling and TCP tunneling more specifically, enabling secure and efficient data transmission. CNHF’s fast link establishment enhances IP protocol performance which extends the practical reach of IP networking into the HF domain.
Learn in this article how IP over HF capability enables efficient and secure data transmission with field tested results.
The challenge: Traditional IP protocols meet HF reality
Standard IP protocols were designed for high-speed, low-latency networks with consistent connectivity. TCP protocols rely on timely acknowledgments and fast handshakes, while many applications expect near-instantaneous responses. When these protocols encounter the high-latency, variable conditions of traditional HF radio, they often fail or perform poorly.
This creates a critical gap in critical communications. Organisations operating in remote areas or contested environments cannot simply abandon their sophisticated IP-based systems when they move beyond the reach of conventional networks. They need seamless integration between their tactical IP networks and beyond-line-of-sight communications.
CNHF technology bridges this gap by providing protocol-transparent IP communication over HF links, enabling real-time operations that were previously impossible in the HF domain.
CNHF technology works in remote areas or contested environments
How CNHF enables IP over HF
KNL’s approach to IP over HF introduces the unique capabilities of our cognitive radio technology. Unlike traditional HF systems that struggle with IP protocols, CNHF radios provide:
Fast Link Establishment. CNHF radios can support IP protocols that depend on timely exchanges, with connection setup times measured in hundreds of milliseconds rather than minutes. This responsiveness is critical for applications requiring real-time reporting in mission-critical communications.
Optimised protocol handling. Our system supports multiple approaches to IP traffic, optimising for different types of applications and protocols:
- UDP Tunneling with unicast, multicast, and broadcast delivery protocols like JREAP and applications such as ATAK to function seamlessly.
- TCP Stream Tunneling forwards raw TCP streams through HF ARQ protocol, enabling reliable operation of HTTP GET requests and similar client-server protocols.
- Full IP Routing preserves complete IP headers, allowing secure protocols like IPsec to maintain their authentication and encryption integrity.
When reasonable, the system performs built-in compression before transmission, reducing airtime requirements and improving effective throughput in bandwidth-constrained conditions.
Real-World Applications: Proven in the field
The practical implications of IP over HF extend far beyond technical specifications, as field tests show.
Situational Awareness Systems
Field tests confirm that Cursor on Target (CoT) messages transmit reliably over HF networks. Testing with up to 30 concurrent clients demonstrates support for blue force tracking scenarios where multiple units broadcast position and status updates beyond-line-of-sight distances.
C4ISR and Network Integration
CNHF Manpack radios provide multiple connectivity options including Ethernet, built-in WLAN, and VPN support. Field testing has confirmed that UDP tunneling operates reliably even through VPN connections, enabling secure integration with existing command networks.
The IP capabilities work alongside existing communication interfaces like SMTP and XMPP, providing comprehensive connectivity options for C4ISR systems and tactical networks.
Built-in Security
All data transmitted over HF links uses AES-256 encryption, ensuring secure communications without requiring external security devices.
For organisations requiring higher security classifications, the IP routing capability allows direct connection of national encryption devices. This enables users to apply their own security standards and maintain full control over encryption levels.
These results are based on field trials conducted by KNL using CNHF1 radios with IP networking over HF.
KNL radios have been proven in the field
The cognitive advantage
What makes IP over HF truly effective in CNHF systems is the underlying cognitive radio technology. Traditional HF radios cannot reliably support IP protocols because they lack the intelligence to adapt to changing conditions.
CNHF radios automatically select optimal frequencies from the available spectrum—field testing showed usage of 481 unique frequencies over 12 hours, with the system adapting to propagation conditions in real-time.
The system’s ability to establish links in 0.5 seconds enables interactive applications that would be impossible with conventional HF automatic link establishment systems.
Summary: IP over HF
The results demonstrate that modern HF platforms like CNHF provide viable IP-based communication over HF links without relying on external infrastructure. Both UDP and TCP service modes were successfully tested under real-world conditions.
- Fast link establishment enhances IP protocol performance with connection times under 1 second
- Scalable multicast UDP: reliable support with delivery rates suitable for operational needs.
- Reliable TCP performance achieved dependable end-to-end delivery with goodput reaching several kilobits per second
- Cognitive frequency selection ensures optimal performance under varying conditions
- Proven protocol support for HTTP and MQTT-based applications
- Built-in security with AES-256 encryption for all transmissions
These results show that IP over HF works reliably in real-world operations without requiring existing infrastructure.
Contact us to hear more
Are you interested in extending your critical communications capabilities? Contact us to learn more.
