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Re: [ppml] Fw: ":" - Re: Proposed Policy: 4-Byte AS Number Policy Proposal


From: Robert Bonomi <bonomi () mail r-bonomi com>
Date: Wed, 14 Dec 2005 08:34:11 -0600 (CST)


From ppml-bounces () arin net  Wed Dec 14 04:30:07 2005
To: ppml () arin net
From: Michael.Dillon () btradianz com
Date: Wed, 14 Dec 2005 10:32:06 +0000
Subject: [ppml] Fw: ":" - Re: Proposed Policy: 4-Byte AS Number
      Policy  Proposal

I'm also not thrilled with "2-byte only" and "4-byte only" ASN; there's 
too
much chance of confusion with "2-byte" and "4-byte" ASNs which have a
different enough meaning to warrant a better distinction.  I'd prefer
something like "legacy" vs. "expanded", "low" vs. "high", etc.

That's an example of the lack of plain English in the 
proposal. Why don't we just talk about AS numbers greater
than 65535 or AS numbers less than 65536?

Because there is more to it than just that.  :)

there is the matter of whether they are represented by 2 bytes, or 4 bytes
_in_transmission_.   '0x00004F4F' is a '4-byte' AS number that has a value
less than 65,536.  It _should_ be treated identically with the 2-byte AS 
number '0x4F4F', as I understand the currently-proposed methodoloty, but 
there is no intrinsic reason why that _must _be the case.  A two-byte AS 
number, and a 4-byte AS number with the SAME numeric value, _are_ 
distinguishable as =different= entities.

1. ARIN begin allocating AS numbers greater than 65535
to those who specifically request them starting on $date.

2. On $date ARIN will not allocate AS numbers less than
65536 unless a small number is specifically requested.

3. On $date, ARIN will no longer make a distinction
between AS numbers less than 65536 and larger ones.

Guess what? I said it in plain English so I don't have to 
define what is an "AS number less than 65536" or an "AS number
greater than 65535". I also don't have to invent silly new
notations so that AS2 looks different after the change. 
A number is a number is a number.

Is it?  <grin>

Do you represent AS 17 in two bytes, or four?  

if you use 2 bytes, do you, "somewhere down the road", change to representing
it with 4 bytes?  or do you deal with 'mixed-length' codes "in perpetuity"?


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