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Re: 3177-bis
Hi Fred,
On Tue, 18 Mar 2008 09:29:39 -0700
Fred Baker <fred@cisco.com> wrote:
> </chair>
>
> On Mar 18, 2008, at 7:41 AM, Tony Hain wrote:
>
> > It appears you missed the point, I was not arguing that we can't
> > revise
> > documents, I was pointing out that we are being asked to revise a
> > document
> > because the RIRs are not willing to do what they need to.
>
> personally, I don't think that's the case. You saw my earlier message
> in another thread that said I thought that there were business cases
> for the use of /64, /60, /56, /48, and /44. I don't see a strong
> argument that one size in fact fits all, or that there should be.
>
As an operator, as somebody who'll be making recommendations and
probably decisions about what size prefixes my employer gives to our
primarily residential customers plus some SOHO customers, and as
somebody who's been "spoilt" by IPX in the past, I *really* like the
simplicity of a single, common prefix length for nearly all customer
end-sites.
An example of why "much" bigger than necessary can be useful is the
roads we drive on (courtesy of Linus Torvalds, when describing why
64 bits on a PC are better than 32 even though most people don't need
4GB+ of RAM). We build roads (and the lights and bridges over them)
that aren't actually sized for the common case of cars. We size them
for the occasional, yet common enough but much larger vehicle i.e.
trucks / semi-trailers etc. As an example, if you think about
the amount of extra steel that is and has been used to make lights over
the roads higher to suit this occasional rather than regular traffic,
that's a very large additional expense that is mostly distributed
across all road users, even though most of these road users won't ever
directly benefit, because they'll never own or even drive one of these
large trucks.
While I don't own a large truck, and can question why I'm paying for
these additional overheads without direct benefits, every now and then
I need to move house, buy groceries or buy furniture. That's where I
do indirectly benefit from wearing this expense, because all of these
goods are transported in these large trucks. In the case of groceries,
I indirectly benefit every week. The indirect and hidden benefits when
I'm not using the roads are of far more value to me than the direct
ones when I myself use the road.
I see the single /48 allocation size in that light. Yes, too big for
most people, most of the time. However, /48 for nearly every end-site
might be providing more indirect benefits to all end-users/end-sites as
a whole rather than direct benefits to the individual. I know that
managing two end-site prefix lengths /48s and /56s will probably double
my employer's end-site addressing management costs. Two end-site prefix
lengths also creates twice as many opportunities for mistakes as a
single prefix length. A single prefix length means reduced end-site
addressing costs, which will likely be a fairly significant indirect
benefit that can (or may, depending on the business people :-) ) be passed
on to all end-sites.
Regards,
Mark.