[179251] in North American Network Operators' Group
Re: Small IX IP Blocks
daemon@ATHENA.MIT.EDU (Charles Gucker)
Sat Apr 4 22:28:05 2015
X-Original-To: nanog@nanog.org
In-Reply-To: <31685005.14783.1428194111120.JavaMail.mhammett@ThunderFuck>
Date: Sat, 4 Apr 2015 22:28:00 -0400
From: Charles Gucker <cgucker@onesc.net>
To: Mike Hammett <nanog@ics-il.net>
Cc: NANOG list <nanog@nanog.org>
Errors-To: nanog-bounces@nanog.org
I've been involved in IX renumbering efforts because exchange(s)
decided to use /25's instead of /24's. It's painful because
troubleshooting can be a little difficult as differing subnetmasks are
in play. If you have the address space, use a /24. ARIN has IPv4
address space specifically reserved for the use by IXPs.
charles
On Sat, Apr 4, 2015 at 8:35 PM, Mike Hammett <nanog@ics-il.net> wrote:
> Okay, so I decided to look at what current IXes are doing.
>
> It looks like AMS-IX, Equinix and Coresite as well as some of the smaller=
IXes are all using /64s for their IX fabrics. Seems to be a slam dunk then=
as how to handle the IPv6. We've got a /48, so a /64 per IX. For all of th=
ose advocating otherwise, do you have much experience with IXes? Multiple p=
eople talked about routing. There is no routing within an IX. I may grow, b=
ut an IX in a tier-2 American city will never scale larger than AMS-IX. If =
it's good enough for them, it's good enough for me.
>
> Back to v4, I went through a few pages of PeeringDB and most everyone use=
d a /24 or larger. INEX appears to use a /25 for each of their segments. IX=
Australia uses mainly /24s, but two locations split a /24 into /25s. A cou=
ple of the smaller single location US IXes used /25s and /26s. It seems the=
re's precedent for people using smaller than /24s, but it's not overly comm=
on. Cash and address space preservation. What does the community think abou=
t IXes on smaller than /24s?
>
>
>
>
>
>
> -----
> Mike Hammett
> Intelligent Computing Solutions
> http://www.ics-il.com
>
>
>
> ----- Original Message -----
>
> From: "Brendan Halley" <brendan@halley.net.au>
> To: "Mike Hammett" <nanog@ics-il.net>
> Cc: nanog@nanog.org
> Sent: Saturday, April 4, 2015 6:10:34 PM
> Subject: Re: Small IX IP Blocks
>
>
> IPv4 and IPv6 subnets are different. While a single IPv4 is taken to be a=
single device, an IPv6 /64 is designed to be treated as an end user subnet=
.
> https://tools.ietf.org/html/rfc3177 section 3.
> On 05/04/2015 9:05 am, "Mike Hammett" < nanog@ics-il.net > wrote:
>
>
> That makes sense. I do recall now reading about having that 8 bit separat=
ion between tiers of networks. However, in an IX everyone is supposed to be=
able to talk to everyone else. Traditionally (AFAIK), it's all been on the=
same subnet. At least the ones I've been involved with have been single su=
bnets, but that's v4 too.
>
>
>
>
> -----
> Mike Hammett
> Intelligent Computing Solutions
> http://www.ics-il.com
>
>
>
> ----- Original Message -----
>
> From: "Valdis Kletnieks" < Valdis.Kletnieks@vt.edu >
> To: "Mike Hammett" < nanog@ics-il.net >
> Cc: "NANOG" < nanog@nanog.org >
> Sent: Saturday, April 4, 2015 5:49:37 PM
> Subject: Re: Small IX IP Blocks
>
> On Sat, 04 Apr 2015 16:06:02 -0500, Mike Hammett said:
>
>> I am starting up a small IX. The thought process was a /24 for every IX
>> location (there will be multiple of them geographically disparate), even=
though
>> we nqever expected anywhere near that many on a given fabric. Then okay,=
how do
> < we d o v6? We got a /48, so the thought was a /64 for each.
>
> You probably want a /56 for each so you can hand a /64 to each customner.
>
> That way, customer isolation becomes easy because it's a routing problem.
> If customers share a subnet, it gets a little harder....
>
>
>
>
