In this case, the primary source for the data is the remote system. Each time that the ATG application needs to access the data, a command is issued to the remote system. If the command fails to return, then the command is issued to the local repository.
Advantages:
You are sure that the data returned to ATG is up to date, except in cases where the remote system is unavailable. In addition, the existence of the local repository can provide a backup form of the data, in case the remote system is inaccessible.
Disadvantages:
Frequent queries to the remote system can affect the performance of the remote system, which may also be serving functions other than the ATG application.
The need to query the remote system will tend to slow the performance of the ATG application.
See Configuring the Remote-then-Local Model for more details about how this approach could be configured.
