Shim6 vs PI addressing

Owen DeLong owen at
Thu Mar 2 10:21:45 UTC 2006

>> I think that is overly pessimistic.  I would say that SHIM6 _MAY_
>> become a routing trick, but, so far, SHIM6 is a still-born piece
>> of overly complicated vaporware of minimal operational value, if any.
> Vaporware part is true, upto now, operational value is to be seen.
Well... I can only go based on the existing drafts since there's no
running code to base an opinion on, but, my opinion of the drafts
is that it will provide minimal operational value.

It's the wrong answer to the wrong question, in my opinion.

>> Personally, I think a better solution is to stop overloading IDR
>> meaning onto IP addresses and use ASNs for IDR and prefixes for
>> intradomain routing only.
> Did you notice that 32bit ASN's are coming and that IPv4 addresses are
> 32bits? :) Which effectively means that we are going to route IPv6 with
> an IPv4 address space. Or when one would use the 32bit ASN for IPv4:
> routing a 32bit address space with an 32bit routing ID. The mere
> difference
Yes, I am well aware of 32bit ASNs.  However, some things to consider:

1.	Just because ASNs are 32 bits doesn't mean we'll instantly
	issue all 4 billion of them.  The reality is that we probably
	only need about 18 bits to express all the ASNs well need for
	the life of IPv6, but, 32 is the next convenient size and there's
	really no benefit to going with less than 32.

2.	In my current thinking on how to achieve ASN based IDR, we
	would not need ASNs for every organization that multihomes,
	only for each organization that provides transit.  This
	would greatly reduce some of the current and future demand
	for ASNs.

> Yep, 2005-1 fits my idea pretty well. Takes care of the folks needing
> address space now while being able to use it differently later when it
> is needed.
> Though as Joe Abley also mentioned (and I also quite a number of times
> already ;) anyone with even a vague definition of a plan for 200
> customers can get a /32 IPv6 without a problem. Just check the GRH list
> for companies in your neighbourhood who did get it.
True, but, until recently, I was being told that ARIN insisted that the
200 "customers" had to be non-related third parties.  E.g. Chevron
couldn't use all their different business units as 200 customers of
Chevron Corporate IT.  It appears based on some recent allocations that
they may have relaxed that stance.



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