IPv6 Default Allocation - What size allocation are you giving out

Thu Oct 9 05:02:37 UTC 2014

In message <2083423091.131955.1412829918586.JavaMail.zimbra at snappytelecom.net>,
 Faisal Imtiaz writes:
> ======================================
> > > >Only short sighted ISP's hand out /56's to residential customers.
> > > 
> > > I am curious as to why you say it is short sighted? what is the technical
> > > or
> > > otherwise any other reasoning for such statement ?
> > 
> > 256 is *not* a big number of subnets.  By restricting the number of subnets
>  residences get you restrict what >developers will design for.  Subnets don't
>  need to be scares resource.  ISP's that default to /56 are making them a >sc
> ares resource.
> =======================================
> 
> So, this is more of a 'opinion' / 'feel' (with all due respect) comment, and 
> not something which has a (presently) compelling technical reasoning behind i
> t ?

There are thousands of examples of things being designed for the
lowest common denominator.  There are thousand of examples of "this
will never be reached" only to have the thing be reached.  Every
time this happens it becomes expensive to correct.  It causes
operational issues for those on the leading edge.

Your home router should support thousands of internal routes and
be able to hand out thousands of prefixes all in a $50 box.  Memory
is cheap.  It doesn't require lots of cpu to support something like
a house even with thousands of subnets.

If /56 becomes the norm the boxes will end up being designed for
256 subnets rather than the thousands it should be designed for
thousands the hardware is capable of supporting.

This unfortunately is human nature.

> Regards
> 
> Faisal Imtiaz
> Snappy Internet & Telecom
> 7266 SW 48 Street
> Miami, FL 33155
> Tel: 305 663 5518 x 232
> 
> Help-desk: (305)663-5518 Option 2 or Email: Support at Snappytelecom.net 
> 
> ----- Original Message -----
> > From: "Mark Andrews" <marka at isc.org>
> > To: "Faisal Imtiaz" <faisal at snappytelecom.net>
> > Cc: "Sam Silvester" <sam.silvester at gmail.com>, "NANOG" <nanog at nanog.org>
> > Sent: Thursday, October 9, 2014 12:40:07 AM
> > Subject: Re: IPv6 Default Allocation - What size allocation are you giving 
> out
> > 
> > 
> > In message
> > <482678376.131852.1412829159356.JavaMail.zimbra at snappytelecom.net>,
> > Faisal Imtiaz writes:
> > > > A /60, /56, /52 or /48 allows the client to run multiple SLAAC
> > > > subnets (16, 256, 4096 or 65536) and to have the reverse ip6.arpa
> > > > zone delegated on a nibble boundary.
> > > 
> > > Understood...
> > > 
> > > > There is plenty of address space even handing out /48's to everyone.
> > > 
> > > Also Understood.
> > > 
> > > >Only short sighted ISP's hand out /56's to residential customers.
> > > 
> > > I am curious as to why you say it is short sighted? what is the technical
> > > or
> > > otherwise any other reasoning for such statement ?
> > 
> > 256 is *not* a big number of subnets.  By restricting the number
> > of subnets residences get you restrict what developers will design
> > for.  Subnets don't need to be scares resource.  ISP's that default to
> > /56 are making them a scares resource.
> > 
> > Mark
> > 
> > > Faisal Imtiaz
> > > Snappy Internet & Telecom
> > --
> > Mark Andrews, ISC
> > 1 Seymour St., Dundas Valley, NSW 2117, Australia
> > PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org
> > 
-- 
Mark Andrews, ISC
1 Seymour St., Dundas Valley, NSW 2117, Australia
PHONE: +61 2 9871 4742                 INTERNET: marka at isc.org