On 6/21/12 7:52 PM, Mark Felder wrote:
On Thu, 21 Jun 2012 18:39:24 -0500, Rod Whitworth <glis...@witworx.com>
wrote:
It is not a "school of thought" - it is how it is. I have seen one /126
out in the wild but it is very lonely.
I work at an ISP/datacenter. We use /126s for the link net. Handing out
/64's "because you can" is stupid in my worthless opinion :-)
It just make everything less efficient and as IPv6 is all done by the
processor as no ASIC process that IPv6 mess yet, then... well, what ever.
As for the school of though, as Rob said, it's not a school of thought,
it's how the RFC said you should assign them period.
You cold read the RFC 5375 for example, or a few more like 4291, 3587,
and other like it.
The reason why many ISP are assigning different side and not the /48, or
56 in some case, or even the /64 is because the IPv6 does have and would
allow you to actually change ISP without the need for renumbering
depending on the process of IP allocation you use See RFC 4291 for
example. I do not argue the good/ or bad of it. That's a totally
different question.
Plus when you need to carry these routers in your iBGP, or OSPF, or what
ever your poison is, you have lots more small route then needed, etc.
Just think about it, when only IPv4 were available, the ISP at large
wasted it no question asked, now they have more then they could possibly
use regardless how how they might want to waste it, so dong /120, or
/126, or what not to a single customer is NOT because they are all
suddenly conscientious and just wake up, it's because it make them lock
you in and not allow you to easily switch ISP if you get piss and lets
face it, if you run a decent side office, renumbering is and always been
painful.
They don't do it because they like you or are acting responsibly now,
but because they need to find a different way to lock you in.
Same reason why do we have NAT for IPv6!?! Really, who could possibly
need that with the address space we have today.
Nat was invented to compensate for IPv4 depletion, but way to many early
IT guys used it for simple way to provide security setup and forgot how
to do it right. It's just easier for them, however with the higher
bandwidth usage we have today they start to run into problem when NAT is
in use and you see jitter, latency and what not cause by it, but they
are clueless about it.
So, don't get me started on the stupidity of IPv6 and how the assignment
is now done.
Does anyone actually need /64 for a company, or possibly a /56 for a
single house connection as the RFC specify it, not really, and a /64 for
the point to point link, I don't think so, but if we are going to use
ti, then use it as it was designed for with it's pro and cons.
But look at the real reason why /126, or /96, or /120 are given in
Europe a lots specially by France Telecom for example it's not because
they are so brilliant, but that's their way to lock you in with them and
not make it easy for you to renumber and if you ever had to do this for
many computers and multiple subnet, and all, you know what I am talking
about. No one is looking forward to that and in many cases, company do
not change ISP because of that simple fact.
One that that IPv6 made good for users was the possibility to switch ISP
overnight and no need to renumber their address space. BIG ISP cut on to
that and do everything possible to not let you have that choice!
They do not want to improve their service to you so that you do not look
anywhere else for good connectivity, but are working in ways to limit
your choice and pretend to do it under the umbrella of IP conversation
when everyone knows these same ISP wasted IPv4 like crazy before as they
can't manage it properly anyway.
Again, I am not arguing on the merit of IPv6 or flaw of it and there is
plenty, but if you are gong to use it and roll it out, then at a minimum
do it as it is suppose to be done and don't try to create a school of
thought that is not based on merit but on ways to lock people in and
that don't stand on their own justification and merit.
I will grate you this however with how they want the assignment to be
done, they address space is sure getting wasted plenty fast as well,
with size accordingly obviously.
The funny part or sad part depending how you actually understand proper
setup, you will still see countless users using NAT for IPv6 that have a
/48 assigned to them...
How crazy is that!
If you ever realize that NAT does have impact on your network
performance on high bandwidth, just wait when you do this for IPv6 and see.
Have fun, but please read the RFC and don't suggest assignment based on
school of thought. Try to do it right from the start and save you pain
down the road now.
Daniel
