Extending Atomic Cross-Chain Swaps

Cryptocurrencies enable users to send and receive value in a trust-less manner. Unfortunately trading the associated assets usually happens on centralized exchange which becomes a trusted third party. This defeats the purpose of a trust-less system. Atomic cross-chain swaps solve this problem for exchanges of value without intermediaries. But they require both blockchains to support Hash locked and Time locked transactions. We propose an extension to atomic swap for blockchains that only support multi-signatures (multisig) transactions. This provides greater capabilities for cross-chain communications without adding any extra trust hypothesis.