Re: [Softwires] comments on draft-carpenter-softwire-sample-00

[WashamFan <[e-mail]>]

Hi,

Please see inline.

----- Original Message -----
From: Brian E Carpenter <[e-mail]>
Date: Tuesday, September 28, 2010 4:17 am
Subject: Re: [Softwires] comments on draft-carpenter-softwire-sample-00
To: WashamFan <[e-mail]>
Cc: [e-mail]


> Hi,
>  
>  On 2010-09-27 21:05, WashamFan wrote:
>  > Hi,
>  > 
>  > It says,
>  > 
>  >    The SAMPLE server will act as an IPv6 router.  In the simplest case,
>  >    it will forward all IPv6 packets to a default route, except those
>  >    whose destination address lies within the PSAMPLE prefix, which 
> will
>  >    be encapsulated and sent towards the host (CPE) and port 
> indicated by
>  >    the V4ADDR and PN values.
>  > 
>  > 
>  > I think it is not appropriate to assume NAT traversal without
>  > relay can be always successful. 
>  
>  I don't understand your comment. If you have a NAT that you cannot
>  traverse with UDP, you have many other problems, not just a lack
>  of IPv6 connectivity.

I misunderstood. I thought the text implies direct tunnels established
instead of hairpinning via SAMPLE server when SAMPLE client to 
SAMPLE client communication occurs . 

>  > Hairpinning might be always used
>  > for simplicity.
>  
>  Yes, that is the SAMPLE model. And it's a discussion for the
>  community whether or not this is acceptable.
>  
>  > 
>  > I'd like to know the status of the draft, is the WG pursuing this
>  > work?
>  
>  There are three drafts aiming at the same problem, SAMPLE,
>  draft-lee-softwire-6rd-udp, and draft-despres-softwire-6rdplus.
>  Please hold your breath, there's hope of a joint proposal
>  from several authors within a few days.

Is it possible to combine all these efforts? I see 2 major 
difference between  draft-carpenter-softwire-sample-00
and draft-lee-softwire-6rd-udp-02 at least:

1. According to the IPv6 address assignment, SAMPLE
is  to connect isolated IPv6 hosts but 6rd-udp is to connect
both isolated IPv6 hosts and LANs.

2. They are different in terms of IPv6 address assignment
procedure. SAMPLE uses ND but 6rd-udp might use RADIUS,
let's say.

Personally, I think it is meaningful to work on tunneling
IPv6 traversing NAT, but I think we should justify the work
by clarifying how bad Teredo did the job before we reinvent
the wheel.

THanks,
washam


>     Brian
>