What Is a PAC File?

Proxy Auto-Configuration (PAC) is a method used by Web browsers to select a proxy for a given URL. The method for choosing a proxy is written as a JavaScript function contained in a PAC file. This file is usually hosted on a network. Browsers can be configured to use the file either manually or, in Microsoft Windows environments, automatically using Group Policy Objects. More info here

Silo and PAC Files

Silo fully supports PAC files and will utilize the instructions provided in a PAC file to connect through the correct proxy server when connecting.  Silo connects to two servers when connecting, the launch server and the application server.  See the Host Names section here for a list of host names which the desktop may connect to when establishing a connection to the service.