Prevent from ransomware

[hs08]

Hello,

If we only have cisco cat4500 and 9500 as the core switch and C2960x as distribution and access switch, what can we do to prevent ransomware attacked the internal resource?

[marce1000]

   - Use business level (oriented) firewalls on the perimeter , such a Palo Alto or other. It has sufficient strength to block that, 

 M.

[Leo Laohoo]

Not a bl**dy thing.

[Rich R]

If you already have ransomware in the network it's probably too late to do anything.
If it hasn't spread everywhere yet then shutdown switch ports to isolate affected parts completely until they're certified "clean".

If you're looking to implement something as prevention then that's not something you can do just on switches.  It's a total security solution - every single part of the network and IT needs to be included in the solution.

Good summary (and some product links) here: https://www.cisco.com/c/en_uk/solutions/security/ransomware-defense/index.html