IT Observer: Single Sign On with pam_usb

[ Thanks to Scott for this link.

“Single sign on solutions provide an authentication mechanism
whereby a single action of user authorization permits the user to
access all the resources based on his access permissions. The
technique reduces the need to remember multiple user-password
combinations and improves information security strategy.

“In order to achieve single sign on (SSO) authentication under
Linux, the use of pluggable authentication modules (PAM) is