The following papers are result of solving real problems in real applications. Most of them are fully invented by Oleg Andreev, some improve the existing ideas. Papers will be updated when better ideas come along. Feedback is welcome.
The most complete collection of Bitcoin technical terms.
Distribute control over bitcoins between multiple custodians while maintaining absolute privacy. Custodians only authenticate you in person and allow or deny a transaction, but never know the contents of the transaction.
Bitcoin wallets normally require careful backup for only its master seed. The scheme allows to encrypt all external information (payment receipts, notes etc.) using that master seed and automatically upload to one or more hosting services (iCloud, Dropbox, Google Drive) to be automatically downloaded and installed during restore process.
A simple multi-signature scheme for establishing game-theoretic trust between two otherwise untrusted entitites (persons or computer agents). This is a basic building block for many decentralized markets and applications such as Bitmarkets app.
Many end-user Bitcoin applications (e.g. Lighthouse, Bitmarkets app) have to implement a wallet functionality just to use some bitcoins for their operation. This is typically less safe for the user than the wallet he is already familiar with. We propose a set of secure APIs that allow apps to get some bitcoins from the user’s wallet in a secure and flexible manner.
Bitcoin wallet’s master key must be protected against compromise and data loss. We propose a key rotation solution to ensure robust 2FA service protecting the master key.
Blockchain is great for ultimate settlement of ownership, but it does not efficiently scale to billions of regular transactions. We propose an overlay protocol that enables clearing small payments via a decentralized infinitely scalable network of IOU swaps backed by actual bitcoins locked up using Joint Escrow.
Proposal to extend scripting capabilities in Bitcoin via a soft fork that allows access to wider amount of information about transactions and persistent state across contracts to enable massive multi-party execution at low cost.
An co-signing oracle that limits withdrawals could be deployed on the satellite to close the window of opportunity for attack. Oracle generates and stores master key for signing and encryption. Full bitcoin node implementation onboard enables monitoring withdrawals and handling billing directly. Clients store all data themselves, encrypted by the oracle’s key where necessary. Cooperating on-earth systems handle withdrawal notifications and cancellation, while full financial privacy is enabled by end-to-end encryption of all activity between the client and the oracle. TTS detects drastic trajectory changes and destroys all sensitive information in case of meaningful deviation (e.g. hijacking).
Hardware Bitcoin wallets are obvious targets for backdoors. We propose a unified method of auditing any wallet for presence of potential backdoors or bugs. The specification also applies to software wallets executed by general-purpose computers, although these may be more challenging to audit.