[ppml] HD Ratio Applied to IPv4

[Paul Wilson]

For background on the HD ratio, including the justification of this approach
in preference to percentage-based utilisation measures, please see RFC3194.

Paul Wilson
APNIC

> -----Original Message-----
> From: owner-ppml at arin.net [mailto:owner-ppml at arin.net] On 
> Behalf Of Charles Scott
> Sent: Thursday, 14 August 2003 7:02 AM
> To: sigma at smx.pair.com
> Cc: ppml at arin.net
> Subject: Re: [ppml] HD Ratio Applied to IPv4
> 
> 
> 
> Kevin:
>   I'm sorry, I'm just not getting this. It would seem that 
> any particular level of assignment needs to stand on it's 
> own. Why then would more levels of assignment below a 
> particular level make that one level more challenging to manage.
>   Also, the larger the assignment, the larger 20% of the 
> assignment becomes, so it would seem to be easier to manage 
> larger size blocks unless the size of the sub-assignments for 
> some reason become proportionately 
> lager relative to the size of the total block as one manages 
> larger and 
> larger blocks.
>   I don't say the above rhetorically. If there's a good 
> reason to make this kind of adjustment then it should be 
> done. But when we're looking at a potential for significantly 
> large additions of wasted (unassigned) space added to the 
> equation, there should be darn'd good reason for making the 
> change, particularly when it adds an additional level of 
> confusion to the process.
> 
> Chuck
> 
> 
> 
> 
> On Tue, 12 Aug 2003 sigma at smx.pair.com wrote:
> 
> > 
> > > APNIC is looking at applying the HD Ratio system to IPv4 
> > > allocations.
> > > Attached is their draft document discussing the idea.  
> I'm curious what 
> > > people in the ARIN region think of the idea.
> > 
> > The current situation, where 80% utilization is required 
> for any size 
> > block, is more challenging when you have multiple levels of 
> assignment 
> > downstream, subdividing the block, wasting boundary 
> addresses, making 
> > it difficult to ensure that each assignment is well-utilized, etc.
> > 
> > The AD-Ratio idea seems to reverse the situation.  Now things are 
> > smooth for networks with multiple levels of assignment, but 
> waaaay too 
> > loose for simpler networks.  A company which has a /17, for 
> example, 
> > and uses it entirely for their own networking, can now get new 
> > allocations after only 70.22% utilization.  These companies (eg, 
> > datacenters, Web hosts, large workstation clusters, etc) 
> have the best 
> > opportunity for utilization nearing 99%.  This effectively 
> gives those 
> > companies less reason to be efficient.
> > 
> > Is there any way to distinguish the two scenarios usefully 
> and adjust 
> > the idea accordingly?
> > 
> > Kevin
> > 
>