:no:no:no:no
I think u haven't use Panda Free cloud antivirus. That's why u have this misconception.
They also store virus signature on your hard drive just like other antivirus do so that it can use that when you are offline.
Even traditional antivirus also has cloud component for example it is called Kaspersky security Network(KSN) in kaspersky, I am sure other antivirus also has cloud component otherwise antivirus companies cannot block Zero Day attack/malicious web link etc.
It does require internet connection just like other antivirus product i.e. to update virus signature. That's it. :k
So it means u don't need to remain online all the time. :tup
Main problem is advertisement. But you cannot complain that as it's free product. If you can bear that it's nice product. Very light on resource :luv