Peter Gutmann wrote:
[EMAIL PROTECTED] writes:
Take a look at Boojum Mobile -- it is precisely the idea of using the cell
phone as an out-of-band chanel for an in-band transaction.
http://www.boojummobile.com
Banks here have been using it to authenticate higher-value electronic
transactions as well. The way it works is that for transactions with a
combined value over the default floor limit of NZ$2.5K you have to use an
additional PIN sent via SMS to a pre-configured number to authenticate the
session. The PIN authenticates that particular session (not just one
transaction), with a fee of NZ$0.25. It's not perfect, obviously, but that
was seen as the best tradeoff between cost, user convenience, and security.
<grumble>A few years ago I wanted to do this out-of-band authentication as a
research project, and at the time couldn't find anyone interested in it; now
they've paid an arm and a leg for it themselves, sigh</grumble>.
Back when we used to run O2's (then Cellnet) web stuff, we used to
authenticate user accounts by sending random words to their phone. This
was so long ago I can't remember when it was, but certainly > 5 years.
Cheers,
Ben.
--
>>>ApacheCon Europe<<< http://www.apachecon.com/
http://www.apache-ssl.org/ben.html http://www.thebunker.net/
"There is no limit to what a man can do or how far he can go if he
doesn't mind who gets the credit." - Robert Woodruff
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