suggestions about two-factor authentication?

Hi All,

I am reviewing web-security technologies, including two-factor authentication. It would be great if you would help by replying to this message with suggestions about why people with cognitive disabilities would have related difficulties.

My understanding is such authentication requires 2 of 3 independent factors.
The factors are something only the user:

*     knows (e.g., password, PIN, pattern);

*     has (e.g., ATM card, smart card, mobile phone); and

*     is (e.g., biometric characteristic, such as a fingerprint)

John

PS: Source - https://en.wikipedia.org/wiki/Multi-factor_authentication

John Rochford
UMass Medical School/E.K. Shriver Center
Director, INDEX Program
Instructor, Family Medicine & Community Health
http://www.DisabilityInfo.org<http://www.disabilityinfo.org/>
Twitter: @ClearHelper