Encrypted Control Communication - impact?

HI All

I am looking to enable Encrypted Control Communications within our version 9.00 DP environment.

Is anyone able to comment on whether enabling this feature has impact to the performance, speed, or any aspect of the backups associated with it? ..

I assume that the encryption occurs on the Cell during backup which I would assume would hit the CPU quite hard? 

Also are there any addotional network ports to consider when enabliong this?

I have also read that backing up the ECC confirg files before enabling this would be a good practice as a backout of anything failed etc?

Any comments or info would be appreciated

Thanks