Digitally Signing and Encrypting Email.
You have configured your email client to
use a digital ID to sign and
encrypt email massages. But before using it, it is necessary to understand
some important things about public key cryptography.
If you have
your digital ID and a private key associated with the digital ID,
then you are able to send digitally signed email messages to your friends
and receive encrypted messages from them.
signed message contains:
1. A message subject and body
2. A digital signature of the message
3. Your digital id with your
email and your public key.
You can obtain a
digital ID from these sources.
Most are a paid service.
DocuSign – Get
a free trial.
Comodo – Learn more and get a free certigicate.
GlobalSign – See website for more information.
GeoTrust - See
website for more information.
There are two
types of keys used in email encryption:
If you have any questions or comments, click
1. Your private
key – this key is used when you sign your message and decrypt the
encrypted messages received from your friends
2. Your public key – is
used by your friend (or any other person) to verify your signature and to
encrypt a message for you.
Thus, your friend will be able
to encrypt messages he sends to you only after he receives a digitally
signed message from you once. This
means that your friend will use your public key that is in your
digital ID to encrypt email
messages for you. And only you will
be able to decrypt these messages using your private key (secret key).
So, if you want to get encrypted messages from your friend, you must
send a digitally signed message to him once.
This will provide him/her with you
IS for future messages, so your friend must
add your digital ID from your email
to his address book (usually it's enough to simply add your contact to
his address book).
On the other hand, if you want to send
an encrypted message to your friend, then
he should send you his digital
ID. After that, you will
be able to encrypt email messages for him using his public key that is in
his digital ID. And only your
friend will be able to decrypt these messages using his private key
Therefore, if you have your digital ID
and a private key associated with the digital ID
and you have a digital ID of
your friend, you are able to send encrypted and digitally signed messages
to your friend. In other words,
you and your friend should send a
digitally signed message to each other once and
add the digital IDs (normally, contacts) to your address books.
To sign and/or encrypt a message in Outlook or Outlook Express you
should open a new mail message window, type your new message subject and
body, click the "Digitally sign message" button and/or "Encrypt message"
button on the top of the new message window.
After that, you may send the
message and it will be digitally signed and/or encrypted.