DosIgriegas writes "The obsession with firewalls in IPv6 may result in some of the quirks of IPv4 reappearing. Ars Technica has an article looking at the topic in depth, exploring the technical challenges of securing the new protocol, and looking a the re-emergence of old problems in new guises. 'Ironically, what's required to make IPv6 work through a stateful firewall is almost identical to what's required to make IPv4 work though NAT. This means the IETF's efforts to keep IPv6 NAT-free in order to make protocols do their job without messy workarounds are defeated by the notion that everything should be firewalled.' If we decide to stick with firewalls in IPv6, we'll see many of the same hard-to-diagnose network problems that we have with IPv4."