Re: [addr-select-dt] Proposed default policy table

Tim Chown <tjc@ecs.soton.ac.uk> Mon, 12 July 2010 21:56 UTC

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Subject: Re: [addr-select-dt] Proposed default policy table
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On 12 Jul 2010, at 10:23, Arifumi Matsumoto wrote:
> 
> On 2010/07/12, at 16:01, Mohacsi Janos wrote:
>> 
>> I think 6to4 and teredo should be treated similarly - after ipv4. They should be used as a last resort acess to IPv6 resources. I think 6to4 should be kept since 6to4 is the most implemented IPv6 of the CPE equipments.
>> 
>> Best Regards,
>> 		Janos Mohacsi
> 
> I agree.
> It is clear to me that there is no longer preferences for 6to4 over IPv4, as well as preferences for Teredo over IPv4.
> 
> But, between 6to4 and Teredo, I tend to prefer 6to4.
> Especially 6to4 host to 6to4 host communication is direct, there are some essential reasons to prioritize 6to4 over Teredo.

The problem with 6to4 is its inherent unreliability unless both communicating parties have ISPs that have 6to4 relays, and even then it can be problematic.    Yes, host to host is different, but it's hard to recognise that usage in a predefined policy table.

Tim