Comment by da_chicken
4 days ago
> SNAT absolutely has intrinsic features that are utilized for security purposes.
Yes, but those features aren't there because they're security features. They're incidental to how NAT functions. It's not inherently secure. The intention of the design is to permit hosts on a network that is not Internet-routable to be able to send traffic that is Internet-routable. That's not a security feature. That's allowing traffic to pass that would ordinarily get black-holed.
> A statefull SNAT implementation itself has most of the characteristics of a "firewall".
Sure, but you should recognize that that's the same as saying a stateful SNAT implementation is an incomplete stateful firewall.
If your goal is to use private addresses, you should use NAT. The point is that if your goal is security, then you should configure a firewall.
Don't expect software that isn't designed to provide you security to provide you with any security.
SNAT is often a feature built on a network stack that also provides other "firewall" functionalities like filtering packets. Configuring SNAT is configuring a firewall? Or is only dropping packets a firewall? Or does the device need "firewall" printed on it? Does a device that has "firewall" printed on it still count as a firewall if it's not configured to filter packets? What type of filtering makes it a firewall? If an SNAT implementation drops packets is it a firewall? Is a linux/windows/bsd box with multiple interfaces a firewall? What if I slap "firewall" label on the box; a firewall now?
SNAT can be used to mask source IP and that can absolutely be utilized strategically as a layer of "security".