Unique identifier for a transaction

A method comprising:

• receiving, by a first transaction manager in first transaction domain of a plurality of transaction domains that include respective transaction managers that own corresponding transactions, a request from a requester to begin a first transaction;
• in response to the request, generating, by the first transaction manager, a unique identifier based on a domain identifier of the first transaction domain and a transaction identifier generated by the first transaction manager for the first transaction;
• and
• sending, by the first transaction manager to the requester, the unique identifier for use by the requester.

An article comprising at least one non-transitory machine-readable storage medium storing instructions that upon execution cause a system to:

• generate unique identifiers for transactions in the system comprising a plurality of transaction domains that include respective transaction managers, each of the unique identifiers being based on a domain identifier of a respective one of the transaction domains and a local transaction identifier generated for the respective transaction by the corresponding transaction manager, wherein the transaction managers own the respective transactions and do not interact with each other in management of the transactions;
• receive, by a first of the transaction managers, registration requests to register resource managers involved in a first of the transactions, the resource managers to manage respective resources with respect to which the first transaction is to be performed, the registration requests sent to the first transaction manager based on the unique identifier of the first transaction;
• and
• receive, by the first transaction manager, a request to commit or rollback the first transaction, the request to commit or rollback sent to the first transaction manager based on the unique identifier of the first transaction.