A computer implemented method for access control for a restricted resource in a computer system, the restricted resource including one or more of: a computing resource; a software resource; and a data store, the method comprising: receiving a first set of records for the computer system, each record detailing an occurrence in the computer system during a training time period when the resource is accessed and the access is authorised; generating a sparse distributed representation of the set of records to form a training set for a hierarchical temporal memory; training the HTM based on the training set in order that the trained HTM provides a model of the operation of the computer system during the training time period; receiving a request to access the resource by a resource consumer; allocating a predetermined quantity of cryptocurrency to the consumer, the allocation being recorded by a blockchain data structure accessible by a network, the blockchain storing digitally signed records validated by network connected miner software components; receiving a second set of records for the computer system, each record detailing an occurrence in the computer system during an operating time period for the computer system in use by the consumer of the resource; generating a sparse distributed representation of the second set of records to form an input set for the trained HTM; executing the trained HTM based on the input set to determine a degree of recognition of the records of the input set; and responsive to a determination that a degree of recognition of one or more records of the input set is below a threshold degree, generating a blockchain transaction to expend at least a portion of the cryptocurrency allocated to the user; responsive to a determination that a quantity of cryptocurrency allocated to the user is below a threshold quantity, identifying the consumer as unauthorised to access the resource. receiving a first set of records for the computer system, each record detailing an occurrence in the computer system during a training time period when the resource is accessed and the access is authorised; generating a sparse distributed representation of the set of records to form a training set for a hierarchical temporal memory; training the HTM based on the training set in order that the trained HTM provides a model of the operation of the computer system during the training time period; receiving a request to access the resource by a resource consumer; allocating a predetermined quantity of cryptocurrency to the consumer, the allocation being recorded by a blockchain data structure accessible by a network, the blockchain storing digitally signed records validated by network connected miner software components; receiving a second set of records for the computer system, each record detailing an occurrence in the computer system during an operating time period for the computer system in use by the consumer of the resource; generating a sparse distributed representation of the second set of records to form an input set for the trained HTM; executing the trained HTM based on the input set to determine a degree of recognition of the records of the input set; and responsive to a determination that a degree of recognition of one or more records of the input set is below a threshold degree, generating a blockchain transaction to expend at least a portion of the cryptocurrency allocated to the user; responsive to a determination that a quantity of cryptocurrency allocated to the user is below a threshold quantity, identifying the consumer as unauthorised to access the resource.