Hello!

I'm sorry if those questions seem trivial, couldn't find a direct easy answer.
I'm planning on developing a cryptocommunications tools for iOS, and intend to use your library, as I've had no success using openssl or gnutls, and it looks simpler and easier.

However I'm left wondering about a few things, and I was hoping you may be able to shed some light.

It is my understanding that streaming communications (voice,video) should not use blocking, but non-blocking sockets.
Furthermore, I understand that only DTLS will work with non-blocking sockets (is that correct?).

What I am looking for, is a scenario, where 2 peers (introduced by a mediator/3rd agent) will exchange packets in a non-blocking fashion.
This is the important part for me:

Can client A, connect to client B, using a Client B's public key (for sending), whereas client B will be using his own private key to decrypt packets intended for him?
Vice versa, can client B, reply to client A, using client A's public key, and client A, decrypting using his private key?

I imagine this is a common scenario using RSA keys (gpg,pgp), but is this a scenario possible with DTLS?

Furthermore, can I, using yassl, generate those private & public keys on the actual iOS device, or should I rely on the mediator to generate those certificates?

If the above scenario is not possible, can you recommend any alternatives?

Looking forward for your answer,
Regards A.