My question is this: I have seen physical firewalls with hosts that can handle several hundred thousand regular concurrent connections but only several hundred concurrent ssl connections. In general, does scalability of physical firewalls deteriorate heavily with https vs http? Especially given that around 90% of all logged in users to the site will have a open connection to the server using the ape-engine for real-time data. If so, what options are there for firewalls to handle this situation properly for ssl while still allowing for scalability?
I understand the open ended nature of this question. What I am really just looking for what experiences other developers have had with such situations, how they have handled it, and what kind of hardware they have found useful in such cases. I can recode the site for https and http usage, but that's a last ditch option.
btw: The site is running on a LAMP stack. It will have to scale to around 1 million concurrent users so scalability really is important. (Let's not turn this into a debate about "your site will never get that large")