A two-way peg bridging BTC to other chains. It works similar to a perpetual one-way peg; however, instead of burning the BTC they are locked up until a particular time in 20 years.
Until then, the community has to figure out how to do peg-outs with, e.g., some sort of OP_ZKP_VERIFY or Simplicity.
We simply pretend that OP_NOP10 is OP_ZKP_VERIFY and let users lock BTC in the following script:
<program_hash> OP_NOP10
OP_CLTV OP_2DROP
https://blockstream.info/block/00000000d1145790a8694403d4063f323d499e655c83426834d4ce2f8dd4a2ee
https://blockstream.info/tx/f4184fc596403b9d638783cf57adfe4c75c605f6356fbc91338530e9831e9e16
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
This document outlines a method to map a secret scalar value x from one elliptic curve group (secp256k1) to another elliptic curve group (a pairing-friendly curve).
This method leverages a variation of the Schnorr signature scheme to prove that the same secret scalar is used in both groups without revealing the value of x.
This approach can be useful in applications where compatibility with different cryptographic groups is required. For example, in the context of using the Lightning Network to purchase in a PTLC a key to be used with pairing-based cryptography. In general, it is interesting for Adaptor Signatures, Scriptless Scripts, and Discreet Log Contracts.
Sats4Files is a protocol for decentralized file hosting. It allows users to request data from untrusted servers, and upon receiving the encrypted data, they can pay for the decryption key via Lightning. The exchange is atomic, ensuring that the user only receives the data if they pay for it, and the seller only gets paid if they deliver the data. The protocol is an efficient form of verifiable encryption, which is similar to verifiable secret sharing using Shamir's algorithm.
This scheme is simplified and does not fully solve the problem, as discussed in the Limitations section. This writeup intends to spark interest to solve the remaining issues beyond the fixes that we suggest.
The client wants to buy from the server the file corresponding to a particular file_id.
Here, we assume we have PTLCs on Lightning instead of HTLCs. That means we can buy a discrete logarithm over Li
The client wants to buy from the server the file corresponding to a particular file_id. The following is a very basic scheme solving the problem in a naive way.
file gets chunked into 32-byte chunks. They are hashed into a Merkle root, which is the file_id.
A decentralized file hosting protocol in which clients pay per request. Client and server perform a fair exchange of coins against files, using a Lightning payment combined with a proof of encryption. This document describes a naive system which is probably too slow, however it intends to spark a discussion about which proof systems could make it practical, because that could allow to decentralize the web.
A “Sats4Files protocol” allows users to request data from servers, and upon receiving the encrypted data, they can pay for the decryption key, e.g., via Lightning. The exchange is atomic, ensuring that the user only receives the data if they pay for it, and the seller only gets paid if they deliver the data.
Servers respond to client requests with a zero-knowledge proof, which expresses
Edit: here you can find our research paper describing the protocol more in-depth.
zkCoins is a novel blockchain design with strong privacy and scalability properties. It combines client-side validation with a zero-knowledge proof system. The chain is reduced to a minimum base layer to prevent double spending. Most of the verification complexity is moved off-chain and communicated directly between the individual sender and recipient of a transaction. There are very few global consensus rules, which makes block validation simple. Not even a global UTXO set is required.
In contrast to zk-rollups there is no data availability problem, and no sequencer is required to coordinate a global proof aggregation. The protocol can be implemented as an additional layer contained in Bitcoin's blockchain (similar to RGB[^5] or Taro[^6]) or as a standalone sidechain.
The throughput scales to hundreds of transactions per
| # The extended euclidean algorithm | |
| def egcd(aa, bb): | |
| lastremainder, remainder = abs(aa), abs(bb) | |
| x, lastx, y, lasty = 0, 1, 1, 0 | |
| while remainder: | |
| lastremainder, (quotient, remainder) = remainder, divmod(lastremainder, remainder) | |
| x, lastx = lastx - quotient * x, x | |
| y, lasty = lasty - quotient * y, y | |
| return lastremainder, lastx * (-1 if aa < 0 else 1), lasty * (-1 if bb < 0 else 1) |
Alice and Bob want to put a token in an offchain contract that expresses:
The problem is that Alice does not want to use any onchain data to reveal the preimage. This is possible with the following setup upfront:
K and encrypts her preimage with that keyK
| // | |
| // SIMD Operation for Bitwise Rotations of Seven UInt32 Values in Parallel | |
| // | |
| %builtins bitwise | |
| from starkware.cairo.common.bitwise import BitwiseBuiltin | |
| // How many bitwise steps do we want to rotate? | |
| // 2**t expresses a rotation of t bits to the right. |