In 2007, Remi Despres, already famous for having designed Transpac–an X25 Network in the 80s, had the idea to customize 6to4 to make a protocol that a Service Provider could use to deploy an IPv6 Service over an IPv4 Backbone.
For a full overview of all the principle Transition Protocols, please refer to this blog:
And this video:
The first popular automatic tunnels were 6to4. 6to4 solved two problems, IPv6 addressing and automatic destination tunnel configuration. 6to4, Connection of IPv6 Domains via IPv4 Clouds, RFC 3056 was published in 2001. It was one of the first transitions to IPv6 protocols after the static tunnels and dual-stack.
It provided the reserved IPv6 prefix, 2002::/16.
Following this prefix the 6to4 gateway was configured for public IPv4 addresses. This way, the destination IPv4 address of the tunnel was coded in the destination IPv6 address. For instance, if a 6to4 Gateway public IPv4 address was 18.104.22.168, the IPv6 site which would be reachable from this 6to4 Gateway would use the prefix: 2002:22.214.171.124::/48 or 2002:c102:405::/48.
Microsoft provided 6to4 relays on the Internet using the IPv4 anycast address 126.96.36.199 for anyone using 6to4 to have access to the IPv6 Internet from IPv4.
The biggest problem with 6to4 for Internet Service Providers is the lack of flexibility due to the fixed 2002::/16 prefix. 6to4 also lacks any basic security features (RFC3964). Because the prefix was not controlled by the Service Provider it was impossible to control the return traffic which would use the closest 6to4 Relay.
To make it suitable for the Service Providers, it was needed to replace the fixed prefix 2002::/16 by a prefix which could be customized by the service providers.
In 2007, Rémi Desprès had this simple idea and went to Free to talk about his idea:
Nov. 7th, 2007: Rémi Desprès knocks on our door
Nov. 9th, 2007: Got IPv6 prefix from RIPE
Nov 10th, 2007: First prototype of 6RD GW and CPE support
Dec. 11th, 2007: Opt-in made available to all of our customers
March 2008: First IPv6-only service : “Telesite
6RD Like 6to4:
Stateless IPv6 in IPv4 encapsulation
6RD Unlike 6to4:
IPv6 prefix rather than fixed 6to4 prefix
Packets from IPv6 Internet entering 6rd GW are only for 6rd customer sites
Provides control over routing return path.
Provides native IPv6 access to home user
For more details about 6RD, Please check out the presentation:
and this video:
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