Esta é uma longa história, iniciada por Phil Zimmermann em 1991. Nas palavras dele: "If privacy is outlawed, only outlaws will have privacy. PGP empowers people to take their privacy into their own hands."
Eu comecei usando PGPi (Pretty Good Privacy, International version) em 1996. Em resumo trata-se da melhor ferramenta para garantir privacidade, autenticidade e integridade no mundo digital. Email e transferência de arquivos podem (e devem) se beneficiar desta tecnologia.
Em 2001 passei a utilizar o GPG, a versão da Free Software Foundation do PGP. Estas são boas referências sobre o assunto:
- Why do you need PGP?
- The GNU Privacy Guard (GPG)
- Surveillance Self-Defense by Electronic Frontier Foundation (EFF)
Aqui está minha chave pública, com a qual assino minhas mensagens e você pode cifrar as suas para mim:
edsilva:~ esms$ gpg --export -a eduardo
-----BEGIN PGP PUBLIC KEY BLOCK-----
Version: GnuPG v1.4.8 (Darwin)
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/0RNysfa
=Yai6
-----END PGP PUBLIC KEY BLOCK-----
edsilva:~ esms$
Minhas chaves anteriores ainda não foram revogadas e, por motivos históricos, ainda encontram-se no pgp.mit.edu.