Distribute database elements
Your question is a little generic / open ended but here's the best I can answer your questions:

&quot;Transaction Processor&quot; is dedicated to tracking the transactions that occur in the primary database on one server so that it can keep distributed databases in sync with the primary database via the &quot;Data Processor&quot;.

It can exist on the primary server or any of the other servers, but usually lives on the primary.

The &quot;Data Processor&quot; is the distributor of the data changes from the primary database to the distributed secondary databases. It's job is to actually move the transactions (or data) from the primary source server and sync it to the distributed secondary servers. It also can live on any of the databases (or its own database) and is usually chosen based on performance reasons.

DDBMS stands for Distributed Database Management System. So it is the very concept / architecture you're asking about. It is composed of multiple databases across multiple servers (usually one server being the primary and the other servers being secondaries). The job of DDBMS is to keep multiple copies of the same database across multiple servers in sync with each other.