Understanding the SBA and the ASM


Not supported by SBC SWe Edge.

A Microsoft Survivable Branch Appliance (SBA) is a device that increases the resiliency of branch office communications during network failures because it is able to switch Microsoft VoIP calls from the network over to the PSTN. Ribbon offers this functionality for Skype for Business and Office 365 Direct Routing within the SBC Edge Portfolio using an Application Solution Module (ASM) that hosts the Microsoft SBA component.

Microsoft prescribed the functionality and security model for the SBA. Ribbon is responsible for the method used to reach the Microsoft recommendation.

The Ribbon ASM operates in either of two modes:

  • In Appliance mode, the SBA utilizes Ribbon's solution to guarantee security and reliability. Ribbon fully supports the ASM (Hardware and Software).
  • In Server mode, the SBA is customized by the customer with a solution not tested or approved by Ribbon. Customization can be for functionality or security purposes. Ribbon does not know the impact of this customization, therefore can only support the Hardware components.

By default, all ASMs are shipped in Appliance mode. Any customization you undertake will turn the ASM into Server mode. The only way to return to Appliance mode is to re-initialize the ASM using the on-board capability via the WebUI.