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throw0101cyesterday at 10:03 PM1 replyview on HN

> Anyhow. I'm not confused about NAT vs. firewalling. No one who dislikes IPv6 is confused by this.

"No one"; LOL. I've participated in entire sub-threads on HN with people insisting that NAT = security. I've cited well-regarded network educators/commentators and vendors:

* https://blog.ipspace.net/2011/12/is-nat-security-feature/

* https://www.f5.com/resources/white-papers/the-myth-of-networ...


Replies

aeonikyesterday at 10:46 PM

That article is making a narrower claim than you're implying. It argues that NAT is not a security mechanism by design and that some forms of NAT provide no protection, which is true.

It also explicitly acknowledges that NAT has side effects that resemble security mechanisms.

In typical deployments, those side effects mean internal hosts are not directly addressable from the public internet unless a mapping already exists. That reduces externally reachable attack surface.

So, the disagreement here is mostly semantic. NAT is not a security control in the design sense, but it does have security-relevant effects in practice.

I personally do consider NAT as part of a security strategy. It's sometimes nice to have.

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