Methods and systems described herein create a first addressed account and a second addressed account that each have a common identifier and are each associated with a customer. The system can receive an order for exchanging digital transactional items associated with the first addressed account, where the order is associated with the common identifier. A private key associated with the first addressed account can be used to electronically sign a first transaction to transfer the digital transactional items from the first addressed account to the second addressed account, and the same private key can be used to sign a second transaction. After verifying that the first transaction was signed with the same private key as the first transaction, the system authorizes placement of the order on a cryptographic exchange.