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What is 6to4 tunnel IPv6?
An automatic 6to4 tunnel allows isolated IPv6 domains to be connected over an IPv4 network to remote IPv6 networks. The key difference between automatic 6to4 tunnels and manually configured tunnels is that the tunnel is not point-to-point; it is point-to-multipoint.
What is the purpose of a 6to4 relay router?
6to4 relay routers function as endpoints for tunnels from 6to4 routers that need to communicate with native IPv6, non-6to4 networks. Relay routers are essentially bridges between the 6to4 site and native IPv6 sites.
What is tunnel mode IPv6?
Tunneling provides a way to use an existing IPv4 routing infrastructure to carry IPv6 traffic. This type of tunnel spans the first segment of the packet’s end-to-end path. Host-to-Host. IPv6 or IPv4 hosts that are interconnected by an IPv4 infrastructure can tunnel IPv6 packets between themselves.
Is there an IPv6 address for tunneling?
This IPv6 address space is only for tunneling and will never be used for IPv6 global unicast addresses. If we start with the 2002::/16 prefix we create a /48 prefix for each tunnel end-point. What we have to do is take the IPv4 address of the end-point and convert it into hexadecimal as bits 17 to 48.
How is a 6to4 tunnel address treated in DNS?
With the automatic generation of 6to4 tunnel address, let us now see the impact it creates further. A 6to4 address is treated as a normal IPv6 address and it gets registered in DNS as AAAA record with dynamic updates enabled at DNS level.
Can a 6to4 router be a border router?
To do this, it uses relay routers which have both 6to4 addresses and native IPv6 addresses. Both border routers and 6to4 hosts can use relay routers but the Anycast 6to4 variant was designed to ease the configuration burden on hosts and small sites.
When does the IPv4 tunnel start with 2002?
The 6to4 tunnel address always starts with a 2002. The remaining digits 836b:1714 are generated based out of the IPv4 address that is configured on the machine and it gets repeated in the interface ID portion also.