Amid remote connectivity gaps in Bhutan’s mountainous geography, Druk Holdings tests an “offline sensor data relay” to a distributed ledger

Bhutan’s sovereign wealth fund, Druk Holding and Investments Ltd (DHI), has pursued digital infrastructure projects amid the country’s mountainous terrain, which often disrupts internet connectivity in remote valleys.

On 19 December 2025, the firm’s “innotech” department addressed these gaps through a pilot enabling sensors in isolated areas to contribute data to a distributed ledger despite lacking direct network access.

​Background: DHI had faced persistent challenges in maintaining reliable data flows from environmental sensors, as mountainous ridges block radio signals and internet outages, hindering real-time logging.

The pressing technology question being investigate: Can a blockchain remain useful when the internet disappears? To examine this, engineers from DHI worked with a vendor of distributed ledger technology to test a system based on the principle of “sign offline, carry physically, verify onchain”. A workflow was piloted to generate verifiable records under such constraints, to gauge the ability to ensure data integrity without constant connectivity.

Key technical concepts
The pilot has demonstrated a resilient workflow where edge devices operate independently of internet access, bridging physical gaps through hybrid relay mechanisms. This approach involved separating data capture and signing from network-dependent verification, enabling seamless integration into a distributed ledger while adapting to Bhutan’s rugged geography. Specifically the pilot involved:

  • Offline signing of sensor data (such as temperature and humidity readings) on low-power microcontrollers
  • Physical relay of tamper-proof messages via drones across terrain barriers to internet gateways
  • On-chain verification and publication once messages reached connected nodes, using a consensus model with parallel execution and low-latency finality

Said Phuntsho Namgay, the firm’s Director of Innotech, this pilot had brought together a highly skilled engineering team alongside local talent, creating a meaningful exchange of expertise and insight: “By applying advanced technology to real challenges shaped by our geography, initiatives like this enable Bhutan to develop solutions with relevance far beyond our borders.”

​According to Kostas Chalkias, Chief Cryptographer and co-founder, Mysten Labs, the technology partner for the pilot: “Theory and practice don’t always align, but for decentralized systems to be global and inclusive, they need to function reliably in environments where constant connectivity isn’t a given. That’s a challenge blockchains need to solve to truly serve the global population…”