Re: Opportunistic Tunneling

[itojun@itojun.org (Jun-ichiro itojun Hagino)]

> As the Unmanaged Analysis document is currently at WG Last Call, the
> biggest issue appears to be the so-called "opportunistic tunneling",
> i.e., automatic tunneling which would be possible without set-up or
> ISP support.  Examples of these are 6to4 and Teredo. (No other
> specific proposals have been made.)  We need to figure out how to move
> forward.  The critical questions are at least:
> 
>  1) Do we agree that this is something we need in the first place?
>      * Considering user-driven deployment, maybe not.
>         - example: the user says "I want to use application X" or "I 
>           want to use functionality Y", where X or Y would require 
>           IPv6.
>      * Considering large-scale vendor-centric deployment, probably 
>        yes.
> 
>  2) What are the models for deploying relays, considering the economic 
>     or deployment considerations (in-host, in-site, network)?
>      * And what are the implications of any approach?
>      * Can we decide on the recommended model?
> 
>  3) For NAT traversing, opportunistic tunneling, are there any 
>     features in Teredo which are missing or are unnecessary? I.e.,
>     how good a fit would it be?  Are there alternatives?

	4) security implication of such technology.  for instance, 6to4 relay
	   router can easily abused.  how about Teredo, and other technologies?

itojun