Oracle GoldenGate Basic Architecture.

Source Database - GoldenGate extracts the information from the source database.
The source database may be from any of the following vendors.

- Oracle Database
- TimesTen
- MySQL
- IBM DB2
- Microsoft SQL Server
- Teradata
- Sybase
- Enscribe
- SQL/MX


Capture(Local Extract) - Capture is the primary process in which all the commited DML and 
DDL changes are extracted from the source database.

Source Trail - The data extracted from the source database is written to the source trail,
which is basically a staging file and will be used by other processes (Ex: datapump).


Datapump - The datapump which is a goldengate process(not to be confused with oracle 
datapump), reads the information from the source trail, transfers it to the target host via 
TCP/IP and writes it down to the remote trail. 

Network - GoldenGate sends the data from the source trail via TCP/IP to the target host
and writes it in the remote trail.


Collector - The collector process is automatically started by the manager. This process
runs in the background, It captures and writes all the data received to the remote trail.

Remote Trail - Remote trail is similar to source trail. The only difference between the
two is that the remote trail is at the target host and the source trail is at the source Database
host.


Delivery(Replicat) - The delivery process applies all the changes to the target database by
reading the remote trail. The changes are done to the target database in the same order as they
were done in the source database.

Target Database - Target database is the database at which all the changes are applied.
It can be same or different from the source database.