Andreas Jellinghaus wrote: > > Do you assume any problems with a generic USB serial number especially > > when using the stick (or several sticks at the same time) with OpenSC? .. > I guess that isn't done and a missing serial is not a big issue.
>From a USB point-of-view, it is a disaster to have identical serial numbers. If you do this, you are effectively making it impossible to distinguish two or more of your devices in the same system, on the system level. In USB, the *only* way to identify a connected device is the combination of vid, pid and serial number. So one of them must be unique if you have any desire whatsoever to distinguish between multiple connected devices in the system. Sure, the five or six software layers in the application (PC/SC, OpenSC, etc) may be able to distinguish the devices by their contents, similar to how two USB memory sticks would be distinguished in a filesystem browser by which files are on them, but that's not useful in the system. The very simplest use case I can think of that is made impossible by having the same serial number in all your devices would be to have user-specific permissions for each connected device. But maybe you don't care. A lot of USB devices do not have valid serial numbers. //Peter _______________________________________________ opensc-devel mailing list [email protected] http://www.opensc-project.org/mailman/listinfo/opensc-devel
