In order to update, Manufacturer Tool builds up a connection either with a specific KNX server directly or indirectly via a proxy. A specific Manufacturer Tool proxy does however not exist, it uses a proxy of the operating system instead. For an English Windows 7 e.g. this can be found under "Windows Control Panel/Internet Options/Internet Properties/Connections/LAN settings".
A proxy with user login is supported if its user is identical to the PC user. In this case, the login for the proxy is passed on to the operating system, given there is internet access.
Manufacturer Tool Updates
Manufacturer Tool Administrative Data Updates