Possible to recreate GPG using pen and paper?

[Harry Rickards]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 06/05/09 19:46, David Shaw wrote:
> On Jun 5, 2009, at 2:52 AM, Harry Rickards wrote:
> 
>>
>> Would it be possible to do the same job that GPG does (using all the
>> same algorithms) simply using a pen and paper? You can do simple
>> public key crypto with RSA, by choosing two primes and doing a
>> multitude of stuff with them. I understand that it will take a while
>> to actually encrypt/decrypt something, and you'll need a calculator as
>> well, but it would be fun to try all the same.
> 
> It is definitely possible.  It might take a while and use a good bit of
> paper, but it's possible.  You would need to understand the public key
> algorithm (RSA, for example) as well as the symmetric cipher (3DES, AES,
> etc).  The actual bytes-in-a-row format is specified in RFC-4880
> (http://www.ietf.org/rfc/rfc4880.txt)
> 
> David
Thanks for the link, I'll have a read through it (although it might take
a while - 28k words). When you say understand the algorithm, do you mean
understand that you take two prime numbers, and multiply them together
to get n, and then multiply them together using the totient function
etc, or understand *why* you take multiply them together using the
totient function etc?

- -- 
Many thanks
Harry Rickards (GPG Key ID:646ED06A)

- -----BEGIN GEEK CODE BLOCK-----
Version: 3.1
GAT/GCM/GCS/GCC/GIT/GM d? s: a? C++++ UL++++ P- L+++ E--- W+++ N o K+
w--- O- M- V- PS+  PE Y+ PGP++ t 5 X R tv-- b+++ DI D---- G e* h! !r y?
- ------END GEEK CODE BLOCK------
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.9 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iEYEARECAAYFAkopba0ACgkQ1kZz3mRu0GoNrgCdEIIIx6tsE33MjB0sQEcMBH6e
ekUAn05V4EbwsYNdZtHtZcoShZj84Wfz
=YSWy
-----END PGP SIGNATURE-----