# Parameter management

The parameter management feature allows to simultaneously update the properties of an application across multiple devices.

Applications on the device comprise a set of executables and configuration files. Configuration files store the application parameters. Parameter attributes for an application are set when a new application is added. The new parameter attributes can also be added or modified to an existing application and downloaded onto the device. The **Parameter Management** feature makes it easier for the user to configure, edit, download, and manage the values of the application parameters. The user can define, configure the parameter values, and download the application (including OS) parameters to the devices.

As a part of the **Parameter Management** process flow, there are two XML files, the Verifone Parameter Form file XML (.vpfx) and Verifone Parameter Definition file XML (.vpdx). The parameter form file lists the parameters, and the parameter form definition file lists the parameters along with the parameter values. The user can configure the parameter values in a vpdx file and upload the parameter definition file that is vpdx file on Device Management to schedule a parameter download onto the device using the **Rollout** feature.

**Parameter Template** provides a convenient way to manage a common set of parameters for a group of devices. The values of the parameters can be changed in a parameter template and uploaded to the associated devices. The parameter templates define values for some or all the parameters of an application. One or more parameter templates can be configured for each application.

The **Parameter Management** feature makes it easier for the user to configure, download and manage the values of these application parameters. The user can define the configuration values and schedule download onto the devices.

The **Parameter Management** feature makes it easy for the user to configure basic and advanced parameters. The user can select the parameters to place them in a basic or advanced file based on the frequency at which the parameters are configured. The user will be able to view and edit the parameters in the basic or advanced parameter list. The user will also be able to schedule a rollout for the configured basic or advanced parameters for a single device or batch devices.

{% hint style="info" %}
Contact the VCS team to upload the user defined VPFX file for basic and advanced parameters.
{% endhint %}

The parameter management feature allows uploading basic VPFX and advanced VPFX files onto Device Management. These files are specific to the application. Even though the user-specific VPFX file is uploaded on Device Management, only the basic parameters that are configured for the specific application version are displayed.


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