Just do it already. The 6bone was built by IPIP tunnels exchanging BGP routes and much of the existing IPv6 Internet still consists of tunnels. Not very complicated at all. Here I'll start with this:
6bone or generic IPv6 over IPv4 tunneling is slightly different:
- ICMPv6 is usually not blocked by "stupid" (or un-informed) firewall configurations - the most commonly used MTU for IPv6 is 1280 which fits very well within tunnels with slightly reduced MTU.
Alot of things will work via tunnels with MTU < 1500 bytes, I'm using them alot for different things for my hobbies, but I have noticed that some things or sites just remain unaccessible in case you cannot deliver ICMP packet-to-big messages reliably or fragment the encapsulation packets.
OpenVPN does a quite good job fragmenting packets without relying on ICMP signalling, I have tried GRE as well but I had better results with OpenVPN.
Of course there might be other solutions, that's why I was asking how did *you* handle issues concerning packet fragmentation etc.
73 de Marc, LX1DUC