Co-op Bank and Verified by Visa

[Clive D.W. Feather]

Andrew Cormack said:
> Since I'm contracted to inform the issuer if anyone ever finds out
> my secret, should I also let them know whenever anyone displays
> knowledge of my birth date, since it's functionally equivalent to the
> secret ???
> 
> One practical implication is that you should never carry a VbV credit
> card and a photo driving licence together :-(

Why only photo driving licence?

Is there anyone here whose driver number does not include their date of
birth encoded in the standard manner [1]? And/or whose licence expiry date
is not the day before their 70th birthday [2]? Or [3].

[1] YMmDdy where Yy is year of birth modulo 100, Mm is month of birth for
males, month of birth plus 50 for females, Dd is day of birth.

[2] Excluding any wrinklies among us, for whom s/70/xx/ where xx = 70+3n
for some n.

[3] In verifying [2], I noticed that my full date of birth is printed on my
non-photo driving licence.

-- 
Clive D.W. Feather          | If you lie to the compiler,
Email: clive at davros.org     | it will get its revenge.
Web: http://www.davros.org  |   - Henry Spencer
Mobile: +44 7973 377646