Re: RFC 3484 Section 6 Rule 9

Joe Abley <> Wed, 04 June 2008 03:07 UTC

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From: Joe Abley <>
To: Brian E Carpenter <>
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Subject: Re: RFC 3484 Section 6 Rule 9
Date: Tue, 3 Jun 2008 23:06:45 -0400
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On 3 Jun 2008, at 17:37, Brian E Carpenter wrote:

> I don't deny that some registries have started allocating PI prefixes
> for large sites.

ARIN is one such registry.

All you need to do to qualify for a direct IPv6 assignment from ARIN  
is to not be an IPv6 LIR, and to qualify for any IPv4 assignment. The  
minimum assignment in such cases is a /48.

All you need to do to qualify for a direct IPv4 assignment from ARIN  
is to demonstrate an intent to be multi-homed. The minimum assignment  
in such cases is a /22. End users need to demonstrate an immediate  
need for a /24, and a projected need for a /23 within a year.

> That doesn't make PI the default model for small and
> medium multi-homed IPv6 sites, which is where our scaling problem will
> lie.

Per above, if you're multi-homed and can justify a /22 of IPv4 space,  
you can get a /48 of IPv6 space as a direct assignment. You can  
qualify for the /22 if you plan to need a /23 within a year. I would  
say that a site that could number its entire operation in an IPv4 /23  
could reasonably be called "small". Note that there is no requirement  
in the policy to use NAT or RFC1918 addresses.

It seems to me that direct assignment could quite possibly become the  
default for small IPv6 sites in the ARIN region. IPv6 uptake to date  
has been so tiny that I don't think anybody can predict what  
behaviours will become prevalent if/when IPv6 takes off.


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