Additional Topics > Medical Imaging in IDL > Using IDL DICOM Network Services > Local Versus System Configuration

## Local Versus System Configuration

There are two modes of configuration available; local configuration and system configuration. Underlying each set of user-defined settings is an .xml file. Changes made to Application Entities (AEs) defined in the system configuration and local configuration mode of the DICOM Network Services utility are reflected in these files.

Note: Always use the DICOM Network Services utility to make changes to the configuration files. The raw .`xml` files should never be modified directly.

The system configuration portion of the DICOM Network Services utility corresponds to a single system configuration file that is used by the Storage SCP service. The Storage SCP service listens for incoming files and is typically started at boot time, which means the service is not associated with a specific user. The properties of the Storage SCP service can only be set when the DICOM Network Service utility is started in system configuration mode.

When you share a single installation of IDL among a number of users, changes made in the system configuration file are visible to all users. In such a network, it is likely that only system-wide configuration information will be entered in system mode, and you will enter individual Application Entity definitions in your local configuration file by starting the utility in local mode. Each user has a local configuration file.

It is important to understand when changes made in system configuration mode are propagated to each user's local configuration file:

- The first time the DICOM Network Services utility is accessed in IDL, the local configuration file is populated with AEs defined in the system configuration file.
- After the first time the utility is started, the local file is only overwritten with system configuration information if the local directory is deleted. In such a case, the local configuration settings will be recreated from the system configuration settings.

If having locally configured AEs that are not duplicated in the system file is acceptable, then there is no need to modify the system file except to define Storage SCP service parameters. This must be done in the system configuration file. See Configuring Your System to Receive Files for details.

Tip: You can use the DICOMEX_GETCONFIGFILEPATH function to return the location of either configuration file. See DICOMEX_GETCONFIGFILEPATH for details.