At Optalysys, we’re shaping the future of secure computing; leveraging silicon photonics to accelerate FHE operations and lay the foundations for the next generation of IT infrastructure. But FHE is a complex topic!

So we asked Joseph Wilson, our Head of Strategic Innovation, to break down the basics of what we’re working on. You can listen to his 10 minute overview below, or scroll on for the write-up.

What is FHE?

FHE is a form of cryptography that allows data to be processed while it is encrypted. This means that sensitive information – like medical, financial or identity records – can be analysed or even shared for collaboration without ever being exposed.

FHE (often heralded as the holy grail of cryptography) allows organisations to utilise their data securely without risking data breaches or privacy violations.

Why is FHE so important? What problems does it solve?

Typically, data is encrypted when it’s stored or in transit, but decrypted when it’s “in use”. Every time data is decrypted, there is a chance it can be stolen or misused.

With FHE, there is no such risk, because the data never needs to be decrypted. It means banks, hospitals, even governments can safely collaborate and gain insights from shared data without ever exposing sensitive information or breaching regulations.

What are the barriers to FHE adoption?

FHE offers absolute security, but at the cost of being incredibly computationally demanding. This means it has historically been too slow and costly to make it a commercially viable solution for real-world use cases.

But this is no longer the case. New technologies, like the specialised hardware developed by us at Optalysys, are designed to accelerate FHE computations by orders of magnitude and move FHE out of the lab and into enterprise data centres.

This performance bottleneck is why our roadmap leads to silicon photonics – computing with light.

What is silicon photonics?

Photonic computing – also known as optical computing – uses light waves (photons) instead of electricity/electrons to move and process information inside computer chips. Light travels at a far greater speed than electrons, meaning that computationally intensive operations, such as those required by FHE, are phenomenally fast.

By using silicon chips as the medium to transmit and process data with light, we’re making these performance gains scalable, cost-effective, and able to integrate seamlessly with digital systems.

How does FHE fit in with other privacy enhancing technologies (PETs)?

FHE is just part of the wider PET mosiac, which includes Zero-Knowledge Proofs (ZKPs), Trusted Execution Environments (TEEs) and Multi-Party Computation (MPC).

Data security and privacy cannot be solved by one technology alone – no single PET is a silver bullet. The power of PETs comes from strategically combining them to effectively tackle the specific task at hand.

FHE might be the most secure, but it can be computationally heavy. Differential privacy, on the other hand, is lightweight but less exact. ZKPs are great for verification, but not for general-purpose computation.

What FHE use cases are the most compelling right now?

Blockchain technology has huge potential across different sectors, but it is transparent by design. This makes it unsuitable for TradFi participation, and puts DeFi users at risk of costly predatory MEV tactics.

Beyond finance, blockchain could be utilised for supply chains, medical records, digital identities and even voting systems. But commercial, individual and regulatory privacy demands require confidentiality on chain.

That’s why we’ve developed LightLocker™ Node – purpose-built to accelerate FHE operations across different blockchain use cases.

FHE is the future

FHE and silicon photonics might sound like science fiction, but together they are paving the way towards a more secure, private and efficient digital world. Across healthcare, finance, medical and defence sectors, FHE allows insights and value to be extracted from a constant flow of protected data.

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