windows mobile 6.5 CAB signing - what is the added value?

Question

I'm developing a Windows Mobile 6.5 application in .NET CF 3.5 for a dedicated customer. The app has implemented functionality of autoupdate. The application asks WebService at startup for a newer version, if one exists, it downloads the CAB installer via HTTP and calls the CAB installation by ShellExecute.
The CAB file is currently not signed. I wonder, what will add CAB signing in case of my application?
The current problem is that when the CAB is installed it requires the user to ack the installation (by choosing where to install and ack that the newer version is to be installed). I wonder whether CAB signing would eliminate those steps?
And another question - we generate updates very frequently (1-2 per week). Does every CAB signing require participation of Microsoft? Can we sign CAB manually?

Regards

Answer 1

Signing the CAB can be done by you, though you need a certificate from a valid cert provider (or the custoemr has to be able to reach your cert server).

However, it will buy you absolutely nothing. Signing the CAB simply allows it to be installed on a device that has security that prevents unsigned CABs from being installed.

The user interaction for the CAB is standard. You can prevent the UI in many cases by shipping your CAb in a package that has an installer EXE that runs wcelaod.exe with the /noui and/or /silent switches.

IIRC, you can avoid the "target folder" dialog by providing a hard destination in the INF file used to generate the CAB.