Bug#971956: release-notes: SANE and driverless scanning
Please consider the following for inclusion in the Release Notes for
Driverless scanning is the ability to scan without using a vendor
backend driver, free or non-free. It is mainly associated with modern
multi-function devices, but some modern standalone scanners are known to
work driverless. "Modern" refers to devices that have been marketed in
the past five years or so.
The official SANE driverless backend is provided by sane-escl in
libsane1 . An independently developed driverless backend is
sane-airscan . Both backends understand the eSCL protocol  but
sane-airscan can also use the WSD protocol . Users should consider
having both backends on their systems.
eSCL and WSD are network protocols. Consequently they will operate over
a USB connection if the device is an IPP-over-USB device . Note that
libsane1 has ipp-usb  as a recommended package. This leads to a
suitable device being automatically set up to use a driverless backend
driver when it is connected to a USB port.