I have some secure data in my website like SSN, Drivers License, along with user name, and password. We are planning to implement SSL. I did a little bit of research and it suggests that you use the SSL only for pages which needs them. Using them throughout the site causes more processing to the server which in case might decrease the performance. I am a little unsure of using it for specific pages as it flags the user as entering and leaving the secure site. If I secure the whole website, will affect the performance significantly? Or is there an alternative way to implement this?
Thanks for your help!