Preventing double login to server

Hello,

 

 

One of my clients would like to do something like following:

 

They have web service where users need to be authenticated against external server such as Radius, before being redirected to the web service page. I think this is possible with ACA module.

 

After logging in, they want to prevent the same user from opening another session at the same time, even if the provided credentials are correct.

 

 

I suppose, in the context of Big-IP, desired behavior is, when a user connects to the web service through the virtual Server on Big-IP, if another session with the virutual server already exists that has been authenticated with the same user, then drop the request or redirect to another page where you are notified that you have another session...

 

 

I am guessing this kind of rule could be complex, since Big-IP need to store session information associated with user name. And every time request comes in, it need to check if sesson of the same user already exists.

 

 

Is this possible with iRule?

 

Any samples where this is accomplished??

 

 

Thanks in advance,