@lexluthermiester I dont know of any instance of IP spoofing on established connections, you can spoof a source ip in one way transmission such as denial of service attacks, but internet usage like using this forum is two way transmission, I have never ever heard of IP spoofing in that regard, its not possible as any ack packets and other returned data will go to the real IP of which you wouldnt receive. So I think that needs to be clear as people might get misunderstood, now you can of course hide your IP by using a proxy server, a VPN, but thats not IP spoofing, then maybe if someone e.g. uses a VPN ip on a ACL, and then that VPN gets compromised sure, but not spoofing.
I also never suggested getting rid of passwords, just I think ACL combined with them is very powerful and indeed you might even be logging into services using soft ACL without even realising it. Steam e.g. uses it combined with passwords. We do agree on the way passwords and other data is stored, the compromises are not down to password usage and could still happen with fingerprints and the like been compromised.
The closest thing to IP spoofing is there is ways to take over an IP block you not authorized to use, but thats more like IP block hijacking, and again you not really spoofing an IP.
In the security industry IP whitelist ACL is considered an extremely good way to restrict authorization but isnt typically used by itself its used in addition to other measures. You can steal password,s fingerprints, etc. but you cannot steal IP's.
Guest Post: I’ll seek to set the record straight for several of the most common misconceptions about IPv6 security.
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