I'm currently doing a project on RSA, and have just come across this website.
On here, it says that
Since encrypted data transmission takes too much time in case of asymmetric encryption, this kind of encryption is used for a secure symmetric key exchange that is used for actual transmitted data encryption and decryption.
Now I was not aware that this was the case, so my question is, does this mean that asymmetric encryption is relatively slow compared to symmetric encryption, or is it impractically slow to be implemented in things like SSL?
Also, out of curiosity, exactly how much slower is it in terms of a time value?
Another question, why do the primes have to be far apart? I guess since the numbers used are so big they are far apart anyway, but is this a prerequisite for RSA, or just a fact that holds due to the size of the numbers?