shim6 @ NANOG (forwarded note from John Payne)

Marshall Eubanks tme at
Fri Mar 3 03:13:41 UTC 2006


On Mar 1, 2006, at 10:45 AM, Joe Abley wrote:

> On 1-Mar-2006, at 10:33, John Payne wrote:
>> On Mar 1, 2006, at 1:52 AM, Joe Abley wrote:
>>> Shim6 also has some features which aren't possible with the swamp  
>>> -- for example, it allows *everybody* to multi-home, down to  
>>> people whose entire infrastructure consists of an individual  
>>> device, and to do so in a scaleable way.
>> Only if *everybody* has a shim6 capable stack...
> Not quite -- the practical usefulness of the multi-homing increases  
> with the deployment of shim6-capable stacks. You could imagine a  
> threshold of server and host upgrades which would provide useful  
> multi-homing a good proportion of the time without universal  
> deployment.
> If Linux and the currently-supported variants of Windows were to be  
> updated to support shim6, and we waited through three or four  
> widely-publicised security vulnerabilities which required OS/kernel  
> upgrades, perhaps that would be sufficient deployment for the  
> benefits of shim6 to be felt, most of the time. My hands are waving  
> again, of course.

I have to object to this here; your hands are not waving nearly hard  

This was exactly the same mistake that was made with IGMPv3, which  
IIRC was
finalized around the time of the Adelaide IETF (i.e., almost exactly  
6 years ago).

1.) It took about 4 years for Windows variants with IGMPv3 support to  
dominate the Windows logs in my web servers.
(By dominate, I mean > 80% of hits from windows machines.) In  
February of this year,
Windows 98 (non IGMPv3 capable) was still 2% of the total web hits,  
compared to 0.56 % for all flavors of Linux and 0.03% for all flavors  
of BSD.

2.) The Mac (8% of web hits in February 2006), still doesn't have it.

3.) So IGMPv3 deployment in hosts _at this instant_ is almost  
certainly less than 90%.

4.) Partially as a result, SSM deployment is still miniscule.

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%  

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.

Marshall Eubanks

> I feel fairly certain I have exceeded some kind of unenforced  
> posting threshold to this list in the last twelve hours. I will try  
> hard to be quiet for a while, now :-)
> Joe

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