Method and system for controlling the performance of a contract using a distributed hash table and a peer-to-peer distributed ledger

A computer-implemented method for controlling the performance of a contract, the method comprising:

• storing a contract on or in a computer-based repository, the contract being associated with a licence between a first user (U1) and a second user (U2), wherein the contract defines a condition which may be evaluated to true or false;
• receiving over a communications network, a transaction comprising a transfer of a token from an agent (A) to the first user (U1) or the second user (U2), the transaction comprising metadata that includes an identifier indicative of a location where the contract is stored;
• querying a peer-to-peer distributed ledger to determine whether the transaction comprises at least one unspent output (UTXO);
• and
• responsive to querying the peer-to-peer distributed ledger, determining whether to modify performance of the contract.

A computer system for controlling the performance of a contract, the system comprising a processing device configured to:

• store a contract on or in a computer-based repository, the contract being associated with a licence between a first user (U1) and a second user (U2), wherein the contract defines a condition which may be evaluated to true or false;
• receive, over a communications network, a transaction comprising a transfer of a token from an agent (A) to the first user (U1) or the second user (U2), the transaction comprising metadata that includes an identifier indicative of a location where the contract is stored;
• query a peer-to-peer distributed ledger to determine whether the transaction comprises at least one unspent output (UTXO);
• and
• responsive to querying the peer-to-peer distributed ledger, determine whether to modify performance of the contract.