oPoW Resources

Towards Optical Proof of Work Michael Dubrovsky (PoWx), Bogdan Penkovsky (C2N, Université Paris-Saclay, CNRS), Lucianna Kiffer (Northeastern University), Marshall Ball (Columbia University)

PDF Link: https://assets.pubpub.org/xi9h9rps/01...

Chinese translation: pdf link

Slides: https://drive.google.com/file/d/1-1rg...

Abridged Litepaper: Link

ScienceX Article: Link

Bitcoin Improvement Proposal: Link

Bitcoin Whitepaper (please read this if you haven’t already): https://bitcoin.org/bitcoin.pdf

Simple model for geographic decentralization vs. CAPEX/OPEX mix in mining costs

oPoW FAQ

*Updated Periodically*

1. Is there reason to believe that the manufacturing of oPoW miners will be more decentralized than ASIC manufacturing currently?

There are no guarantees in decentralized networks, but we think all evidence points to oPoW creating a more decentralized network.

a. Cost of entering oPoW hardware manufacturing will be much lower due to Silicon Photonics using old CMOS nodes (~90 or 220 nm vs. ~7 nm for transistors).

b. Removing electricity prices from the mining equation means that miners do not have to concentrate in regions with cheap power or depend on the sanction of governments that control most energy sources.

2. What other costs would replace energy?

Hardware depreciation

3. Why create Heavy Hash, why not just compute SHA256 optically? This accomplishes the same goal without any changes to the Bitcoin codebase.

Many have tried… there is a large economic incentive. Analog optical computing is limited in the types of computations it can do efficiently. It’s much more feasible to design the PoW around those limitations.

9. When will optical mining hardware be available?

General-purpose photonic coprocessors are being commercialized by multiple companies that have shown interest in supporting mining hardware. Stay tuned for announcements.

10. Is the oPoW algorithm limited to optical devices? If not, will there be miners on the system using digital hardware?

oPoW is reverse compatible with CPUs, GPUs, and ASICs.

11. Is oPoW less secure than SHA256?

oPoW is based on Heavy Hash, a construction that includes SHA3 and inherits all of its security properties. (see Towards Optical Proof of Work above for a cryptographic analysis).

General Optical Computing Resources

*Updated Periodically*

1. Towards Optical Proof of Work M. Dubrovsky et al. (see sections 1.5 and 2.2, pdf link above)

2. Deep learning with coherent nanophotonic circuits Y Shen et al.

3. Matrix Processing with Nanophotonics

4. Photonic Multiply-Accumulate Operations for Neural Networks M. A. Nahmias et al.

5. Lightelligence releases prototype of its optical AI accelerator chip

6. Lightmatter details Passage, a light-based chip interconnect that enables 1Tbps data transfers

Acknowledgments

Alongside the main cocreators of oPoW (Michael Dubrovsky, Marshall Ball and Bogdan Penkovsky), we’d like to acknowledge some of the people that contributed along the way:

Yonatan Sampolinsky, Zao Yang and Lucianna Kiffer at DAGlabs who provided some seed funding for PoWx and a lot of feedback on the game theory/economics
Adam Trigui who provided some seed funding early on for PoWx
Moni Naor (co-creator or PoW and author of Pricing Via Processing) who gave me some feedback very early on in the ideation phase of the oPoW architecture. Mike had an in-person meeting with him when he was living in Israel
Guy Corem who provided a lot of early feedback (he was the founder of the first really successful ASIC mining manufacturer, Spondoolies, that predated Bitmain)
Tom Brand from Technion/Starkware who provided early feedback on the cryptographic construction
Mitchel Nahmias, Nick Harris, and Yichen Shen from Luminous, Lightmatter, and Lightelligence who gave feedback regarding optical computing and its capabilities/limitations as we worked to design oPoW
Diedrik Vermeulen who provided feedback on scalability, manufacturability, and power consumption modeling of silicon photonic chips