IPv6

Tests

Service	Tests Subjects
mythic-beasts.com	Nameservers, Webserver, Mailserver
test-ipv6.com	Connection, DNS Resolver
ipv6-test.com	Connection, DNS Resolver, Reverse DNS, ICMP, Ping, Speed, Webserver

IPv4 World ↔ 192.88.99.16to4 relay2002:x.x.x.x::/48 ↔ IPv6 World
192.88.99.1 is an anycast address of the nearest 6to4 relay
2002:x.x.x.x::/48 is an anycast route of the nearest 6to4 relay
On one side of the IPv4 net is an 6to4 relay, on the other an 6to4 router or host
IPv4 Hosts get an IPv6 Net
IPv6 Hosts get nothing (they know “I'm talking to an 'IPv4 host'” but they don't get an IPv4 IP/Net)
IPv6 encapsulated in IPv4
IPv4(Type=41, Src=x.x.x.x, Dst=192.88.99.1, Payload=IPv6(Src=2002:x.x.x.x, Dst=Dst))
2002::/16 gets an public IPv4 Address appended ⇒ 2002:x.x.x.x::/48 ⇒ 16 Bit remaining for subnets.
Unmanaged: Automatically finds nearest Router per anycast
As an public IPv4 is required, it's hard to NAT

Host		IPv4 only Net	6to4 relay	At least IPv6 Net
At least IPv6 Net	6to4 router	IPv4 only Net	6to4 relay	At least IPv6 Net
IPv6(Src=2002:x.x.x.x::, Dst=y)	→	IPv4(Type=41, Src=x.x.x.x, Dst=192.88.99.1) + IPv6(Src=2002:x.x.x.x::, Dst=y)	→	IPv6(Src=2002:x.x.x.x::, Dst=y)
IPv6(Src=y, Dst=2002:x.x.x.x::)	←	IPv4(Type=41, Src=192.88.99.1, Dst=x.x.x.x) + IPv6(Src=y, Dst=2002:x.x.x.x::)	←	IPv6(Src=y, Dst=2002:x.x.x.x::)

Like 6to4, but with explicitly configured relays (managed)
On both sides of the IPv4 only net are relays or hosts
Both have to configure the IPv4 IP of the other endpoint ⇒ Only usable for static IPv4 addresses.
Not dependent on an 2002::/16 net

Solves the NATing problems of 6in4 and 6to4 by using NATable transport protocols (UDP, TCP, SCTP)
Prevents spoofing by signing packages
Prevents replaying
Does not encrypt packages
Still has problems with dynamic IPv4 addresses (those transport protocols does not support roaming)

Software/Protocol developed by SixXS to make 6in4 and AYIYA usable for dynamic IPv4 addresses (informs the other endpoint about new IPv4 address)
Also used by HE

IPv6 representations of IPv4 addresses
IPv4-Mapped IPv6 Address: ::FFFF:x.x.x.x
- Only on one host
- Use IPv6 API for IPv4 (prevents duplicated or complicated code)
- Can never be seen on the wire
IPv4-Compatible IPv6 Address: ::x.x.x.x(deprecated)
- Can be routed and translated to the corresponding IPv4 (and back???)
- Can be seen on the wire