Hi, I am studying CCNA
and I've just learned some about radius and tacacs+ protocols; and I can't distinguish different protective application layer tools like these and some like vpn and captive portal
I want to know about basic differences and where to use one or another?
does anyone give us things better than other ones?
which is more secure?
if we want to control access to network in a working environment, which is most suitable?
Thanks in Advance.
(Moved to Computer Science forum by @Laura