4 ms·

> Most routers do not filter IPv6 by default. This isn't my experience. If you are correct however, that is a failure of the ISP/CPE provider, not a flaw of IP

> Most routers do not filter IPv6 by default. This isn't my experience. If you are correct however, that is a failure of the ISP/CPE provider, not a flaw of IPv6. > mainly because IPv6's design assumes a per-device firewall I don't see a single mention of firewalls in the RFC[1]. But then neither did the ipv4 spec. Why would we suddenly stop using firewalls though? They have been standard on networks for decades. 1. https://datatracker.ietf.org/doc/html/rfc2460 https://datatracker.ietf.org/doc/html/rfc2460

zinekeller 5y ago
> This isn't my experience. If you are correct however, that is a failure of the ISP/CPE provider, not a flaw of IPv6. First, I'm excluding enterprise firewall here. I've verified this with multiple non-CPE routers, and except for the router itself (for obvious reasons), no, IPv6 traffic isn't really filtered. The "firewall" is laughable on some routers (including some assuming /64 filters which isn't necessarily true for some servers like OVH's). The only non-enterprise one that's working as much as an IPv4 system is Asus'. Some routers tries to filter out DoS attacks. Those are rather confusingly called a "Firewall", but it's not really a controllable firewall per se, allowing "normal" but otherwise a malicious-if-DPIed traffic. A tell-tale sign that this is the "firewall" you have is that you cannot set IPv6 whitelists on your router. > I don't see a single mention of firewalls in the RFC[1]. But then neither did the ipv4 spec. Why would we suddenly stop using firewalls though? They have been standard on networks for decades. The RFC? Yeah, both IPv6 and IPv4 have evolved in the years so that there's multiple RFCs about them. For example, IPv4 don't promote ICMP firewalls but details what ICMP messages must you allow if you deploy one (unless you wholesale block that IP). IPv6 instead never allows you to block any ICMP messages except if you wholesale block an IPv6 address.

zinekeller 5y ago

> This isn't my experience. If you are correct however, that is a failure of the ISP/CPE provider, not a flaw of IPv6. First, I'm excluding enterprise firewall here. I've verified this with multiple non-CPE routers, and except for the router itself (for obvious reasons), no, IPv6 traffic isn't really filtered. The "firewall" is laughable on some routers (including some assuming /64 filters which isn't necessarily true for some servers like OVH's). The only non-enterprise one that's working as much as an IPv4 system is Asus'. Some routers tries to filter out DoS attacks. Those are rather confusingly called a "Firewall", but it's not really a controllable firewall per se, allowing "normal" but otherwise a malicious-if-DPIed traffic. A tell-tale sign that this is the "firewall" you have is that you cannot set IPv6 whitelists on your router. > I don't see a single mention of firewalls in the RFC[1]. But then neither did the ipv4 spec. Why would we suddenly stop using firewalls though? They have been standard on networks for decades. The RFC? Yeah, both IPv6 and IPv4 have evolved in the years so that there's multiple RFCs about them. For example, IPv4 don't promote ICMP firewalls but details what ICMP messages must you allow if you deploy one (unless you wholesale block that IP). IPv6 instead never allows you to block any ICMP messages except if you wholesale block an IPv6 address.