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On 21/03/2011 08:47, Barry Kwok wrote:
<blockquote
cite="mid:AANLkTim6ot+RxqrR5kqyrSmGThtvq0=fX+VcjYmsyZaC@mail.gmail.com"
type="cite">2. Request code
<div>Should it be more easier to dictate over phone If use <b>digits </b>instead.
(eg. 5 digits. I think it is secure enough)</div>
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</blockquote>
It would need to be a lot more than 5 digits. Imagine what happens
if someone tries to break it with 10,000 PCs all trying 5 numbers
per second, which is quite possible. You need to be proof against
massive-scale attacks like that, or they can and will brute-force
it. I would say 9 digits at least. At which point 3 words are
probably more reliably input.<br>
<pre class="moz-signature" cols="72">Jules
--
Julian Field MEng CITP CEng
<a class="moz-txt-link-abbreviated" href="http://www.Zend.To">www.Zend.To</a>
Follow me at twitter.com/JulesFM
PGP footprint: EE81 D763 3DB0 0BFD E1DC 7222 11F6 5947 1415 B654
'All programs have a desire to be useful' - Tron, 1982
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