in reply to Strong Encryption
I agree with most of the individuals who have posted comments on the subject. However it also should be noted that a good merchant gateway provider will also provide a means of setting recurring transactions for subscription purposes. Letting them store the CC number instead of having you do it. The benefit of letting them do this work is that they would have better security to protect the card numbers as well as the fact that if they get hacked, their insurance can pay for any damages incurred if the numbers get stolen and used. Also it saves you time, money, drive space and worry. If your business gets hacked it has a high possibility of ending it.