Does a digital signature enable encryption both ways?

[John Richard Jones]

New to digital signatures & not having used them yet, if I were to send a
digitally signed email and the addressee to include the certificate in my
contact details on their machine, would it be possible for the addressee to
encrypt a message in return to me with this digital signature or would the
addressee also need to get a digital signature and send a digitally signed
email to me with it as well for me to include in their contact details on my
machine?

 

[homeLAN]

Once you have sent a digitally signed message with your certificate to the
addressee, then he can send you an encrypted message without having his own
digital certificate.

But note that you have asked different questions in the body of your post
and its subject. This is not "encryption both ways". To do that, then you
would indeed both need to send eachother a digitally signed message with your
respective certificates.

 

[John Richard Jones]

Does that mean I cannot send an encrypted message to the addressee but the
addressee can send one to me?
I am trying to determine which way the encryption is as I would have thought
my digital signature could encrypt outwards and let the addressee decrypt it
at the other end but you say my digital signature at the other end can
encrypt a message back. This is what I meant by encryption both ways but I
have been given two bits of information partly contradicting the other. One
says I can encrypt outward and you say the addressee can encrypt in return.
I am not used to these discussion groups yet so sorry if I have
misinterpreted.

 

[homeLAN]

If you have my certificate, you can send an encrypted message to me - if I
have your certificate, I can send an encrypted message to you. End of story.