If i receive an email, how does my computer verify the author origin integrity using the digital certificates? Does it use any specific protocol for this?

  • It is unclear what kind of verification you exactly refer to. Usually no verification of the origin is done at all. But there are rarely used protocols S/MIME and PGP which support signed mails and thus make validation of the sender possible. There is also DKIM where the mail server signs a mail which makes at least verification of the senders domain possible. Please narrow down your question and specify what exactly you want to know. – Steffen Ullrich Nov 13 '18 at 6:22
  • @SteffenUllrich I want to know how the user would be able to verify if the message is coming from the right person without any interference from the bad guys. Do digital certificates provide any mechanisms that detect these type of issues? – boomchickawawa Nov 13 '18 at 6:39
  • Like I already said - usually no verification of the origin is done and can be done at all. Prove of origin might be done by signing the mail with certificates or similar using S/MIME or PGP but this requires explicit action on the senders side which is usually not done. – Steffen Ullrich Nov 13 '18 at 6:48