aes1660 driver supports devices based on the Authen``Tec AES1660 chipset.
aes1660 is part of libfprint and is developed by Vasily Khoruzhick.
This device can most commonly be found embedded in some laptops, standalone USB device exists.
Vasily Khoruzhick wrote this driver based on bus traffic analysis and comparison with other Authen``Tec drivers. Bus traffic logs were provided by Andreas Loos. aes1660 shares almost all code with aes2660 driver, they only differ in init sequences and image width.
This is a swipe-type device which is similar to other Authen``Tec devices. Each frame is 128x8 pixels in size.
The fingerprint is always sent unencrypted over the USB bus. Device can encrypt image, but it's not supported. According to traffic logs, control traffic (commands) is never encrypted.
Image processing works well -- fingerprint image quality is good, the enhanced/binarized version is also good, and minutiae detection is accurate. However, this being a small sensor, a relatively small area of the finger is detected, and hence not that many minutiae. This results in low match scores, the threshold of which has been dropped to 25.
Obtaining a good enrollment scan helps the matching performance a lot. It's usable but not brilliant -- false rejections are currently a little more common than we would like.