Description of Application object layers in Microsoft Dynamics axapta

Description of Application object layers in Dynamics

SYS The standard application is implemented at the lowest level, the SYS layer. The application objects in the standard application can never be deleted.

GLS When the application is modified to match country/region-specific legal demands these modifications are saved in a separate layer, the GLS layer. If an application object, for example, a form, is modified in the GLS layer,the modifications are saved in the GLS layer only and the modified version of the form is used.

HFX HFX is an application object patch layer reserved by Microsoft for future patching or other updates.
SL1, SL2,or SL3 A layer where the distributor can implement vertical partner solutions. SL is an
abbreviation for Solution.

BUS When a business partner creates their own generic solution, their modifications are saved in the BUS layer and the top-level application objects are used.

VAR Value Added Resellers (VAR) can make modifications or new developments to the VAR layer as specified by the customers or as a strategy of creating an industry-specific solution. Such modifications are saved in the VAR layer.

CUS The supervisor or administrator of an end user installation might want to make modifications that are generic to the company. Such modifications are saved in the CUS (CUStomer) layer.

USR End users might want to make their own modifications, such as in their reports. These modifications are saved in the USR layer