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Re: bike locks and encryption

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Ben Bacarisse wrote:

> Richard Heathfield <invalid@see.sig.invalid> writes:
> 
>> Ben Bacarisse wrote:
>>
>>> RichD <r_delaney2001@yahoo.com> writes:
>>> 
>>>> Something occurred to me recntly - bicycle locks
>>>> as examples of one way functions, so useful in
>>>> encryption.  That is, easy to compute in encryption,
>>>> but intractable for decrytion, lacking the key.
>>> 
>>> I don't think that's a good analogy for a one-way function.  Although
>>> all one-way functions have, in some very abstract sense, a "key" (the
>>> function's inverse is, I suppose, a key) they are not, usually,
>>> invertable with some small amount of data acting as a key.
>>
>> I think RSA is a counter-example, isn't it? (More on that in a
>> second.)
> 
> I think you (and the OP) might be confusing trap-door functions with
> one-way functions.

My understanding of a trap-door function is that it's easy to compute in one 
direction but hard to compute in the other without a crib (for example, 
RSA).

My understanding of a one-way function is that it's easy to compute in one 
direction but hard to compute in the other without a crib (for example, 
RSA).

So yes, I may well be confusing them. ;-)



-- 
Richard Heathfield
Email: rjh at cpax dot org dot uk
"Usenet is a strange place" - dmr 29 July 1999
Sig line 4 vacant - apply within

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Thread

bike locks and encryption RichD <r_delaney2001@yahoo.com> - 2014-10-06 23:28 -0700
  Re: bike locks and encryption Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-10-07 11:39 +0100
    Re: bike locks and encryption Richard Heathfield <invalid@see.sig.invalid> - 2014-10-07 11:53 +0100
      Re: bike locks and encryption Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-10-07 16:24 +0100
        Re: bike locks and encryption Richard Heathfield <invalid@see.sig.invalid> - 2014-10-07 21:26 +0100
          Re: bike locks and encryption Ben Bacarisse <ben.usenet@bsb.me.uk> - 2014-10-08 01:34 +0100
          Re: bike locks and encryption RichD <r_delaney2001@yahoo.com> - 2014-10-07 23:16 -0700
      Re: bike locks and encryption RichD <r_delaney2001@yahoo.com> - 2014-10-07 23:27 -0700
  Re: bike locks and encryption RichD <r_delaney2001@yahoo.com> - 2014-10-07 13:57 -0700
    Re: bike locks and encryption Kaz Kylheku <kaz@kylheku.com> - 2014-10-07 21:21 +0000
      Re: bike locks and encryption "BartC" <bc@freeuk.com> - 2014-10-07 22:33 +0100
        Re: bike locks and encryption Jongware <jongware@no-spam.plz> - 2014-10-08 15:51 +0200
  Re: bike locks and encryption Kaz Kylheku <kaz@kylheku.com> - 2014-10-07 21:10 +0000
    Re: bike locks and encryption RichD <r_delaney2001@yahoo.com> - 2014-10-07 23:34 -0700
      Re: bike locks and encryption Kaz Kylheku <kaz@kylheku.com> - 2014-10-08 14:10 +0000
        Re: bike locks and encryption RichD <r_delaney2001@yahoo.com> - 2014-10-10 18:33 -0700

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