Site autonomy refers to the effect of one site’s operations on another. There is complete site autonomy if one site’s ability to do its normal work is independent of its connectivity to another site, and independent of the state of operations at that site. For example, the two-phase commit protocol (2PC) makes every data change dependent on every other participating site being able to successfully and immediately accept the transaction. If one site is unavailable, no work proceeds. At the other end of the spectrum, merge replication sites work independently and can be completely disconnected from all other sites. Merge replication has high site autonomy and resulting convergence but does not guarantee data consistency. 2PC has immediate transactional consistency but a total absence of site autonomy. Other protocol solutions are somewhere in the middle for both dimensions.