shim6 @ NANOG (forwarded note from John Payne)

Stephen Sprunk stephen at
Fri Mar 3 16:48:10 UTC 2006

Thus spake "Tony Li" < at>
> Marshall,
>> That's after 6 years.
>> I would be surprised if Shim6 going into actual deployed boxes was any
>> faster.  So, if Shim6 was finalized today, which it won't be, in 2010 we
>> might have 70% deployment and in 2012 we might have 90% deployment.
>> I actually think that 2012 would be a more realistic date for 70%
>> deployment of Shim6, given the lack of running code and a finalized
>> protocol now.
>> In my opinion, that doesn't imply that Shim6 should be abandoned. But it
>> does mean IMHO that regarding it as a
>> means to spur IPv6 deployment is just not realistic.
> Sorry, but I'm just not buying the analogy.  The market drivers for IGMP
> are somewhat smaller than they are for IPv6.

That depends on your perspective.  There's a compelling need for usable 
multicast in many environments, and so far there's nobody (in the US) with a 
compelling need for IPv6, much less shim6.

> Yes, it would take a couple of years for Shim6 to be implemented and
> depending on where we hit Redmond's release cycle, actually
> penetrate a significant number of hosts.

Shim6 needs to be finalized first, then someone has to convince MS to 
implement it.  I'd put that, conservatively, at 4 years.

> 6 years is probably long, and definitely long if we get a confluence of
> panic about the death of v4 plus a strong endorsement about Shim6
> from the IETF.

The most dire predictions of v4's death have it at least 12-15 years away. 
To companies worried about next quarter's profits, you might as well be 
talking about global warming.

> Consider that the IETF *could* conceivably require every compliant v6
> implementation to include it.  I grant that that's unlikely and some
> lesser endorsement is probably more reasonable, but I don't think
> that you should underestimate the capability of the IETF/ISP/vendor/
> host community to act a bit more quickly, if there is sufficient
> motivation.

Without any enforcement powers, an IETF "requirement" is pretty useless. 
Those vendors that care will merely see one more complicated thing they have 
to add to their IPv6 stack and put it off adding IPv6 even longer.

> I suggest that we compromise, split the difference and swag it at 4 years.

His was a minimum; I'd put the likely number at 4-6 years after shim6 is 
finally published (itself no fixed date), and potentially much longer if 
middlebox support is added (and without which shim6 will certainly never see 
the light of day).


Stephen Sprunk        "Stupid people surround themselves with smart
CCIE #3723           people.  Smart people surround themselves with
K5SSS         smart people who disagree with them."  --Aaron Sorkin 

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