An example operation may include one or more of receiving a request to modify a reliability value of an off-chain data source to generate a modified reliability value, determining whether a consensus on the modified reliability value has been received among a plurality of peer nodes, and in response to a determination that the consensus has been received, updating a storage to reflect the modified reliability value associated with the off-chain data source, and storing an identification of the modified reliability value within a block among a hash-linked chain of blocks on a distributed ledger shared among the plurality of peer nodes.