[137733] in North American Network Operators' Group
RE: Internet Exchange Point(IXP) questions
daemon@ATHENA.MIT.EDU (Michael K. Smith - Adhost)
Fri Feb 18 13:45:49 2011
From: "Michael K. Smith - Adhost" <mksmith@adhost.com>
To: "Yaoqing(Joey) Liu" <joey.liuyq@gmail.com>
Date: Fri, 18 Feb 2011 18:43:29 +0000
In-Reply-To: <AANLkTimFEJmZq74D9oXLwBvadwjq9_+ofoQbhc1j4n2J@mail.gmail.com>
Cc: "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
--
Michael K. Smith - CISSP, GSEC, GISP
Chief Technical Officer - Adhost Internet LLC mksmith@adhost.com
w: +1 (206) 404-9500 f: +1 (206) 404-9050
PGP: B49A DDF5 8611 27F3 08B9 84BB E61E 38C0 (Key ID: 0x9A96777D)
From: Yaoqing(Joey) Liu [mailto:joey.liuyq@gmail.com]=20
Sent: Thursday, February 17, 2011 7:04 PM
To: Michael K. Smith - Adhost
Cc: nanog@nanog.org
Subject: Re: Internet Exchange Point(IXP) questions
On Thu, Feb 17, 2011 at 8:17 PM, Michael K. Smith - Adhost <mksmith@adhost.=
com> wrote:
> -----Original Message-----
> From: Yaoqing(Joey) Liu [mailto:joey.liuyq@gmail.com]
> Sent: Thursday, February 17, 2011 6:03 PM
> To: nanog@nanog.org
> Subject: Internet Exchange Point(IXP) questions
>
> I'm doing some research on multiple origin AS problems of IXPs. As I know=
,
> generally there are two types of IXPs
> type 1: use exchange routers, which works in layer 3
> type 2: use switches and Ethernet topology, which works in layer 2.
> So I have a couple of qustions:
> 1. For type 1, the exchange routers may use several IP prefixes for routi=
ng,
> how often does the IP prefixes have their own AS?
> 2. For type 2, all peers connected to the IXP must work in the same subne=
t
> required by Ethernet rules. Is possible that the subnet IP prefixes belon=
g
> to some private IP address space, such as 192.168.x.x? How often does thi=
s
> happen? If the subnet only contains public IP addresses, how are the
> addresses announced?
>
> Thanks,
> Yaoqing
>Hello:
>On the Seattle Internet Exchange (SIX) we have ARIN-assigned addresses tha=
t we use on the Layer 2 fabric (your type 2 above). =A0Hopefully the addres=
ses aren't being announced at all, although >we sometimes have to chase dow=
n people that announce it. =A0Those addresses aren't the destination for an=
y traffic, they are merely part of the transport to a destination, so there=
is no need for >them to be in the DFZ.
>But I just checked the IXP prefix list, and found SIX owns prefix 206.81.8=
0.0/23. And it has been announced by three ASNs, AS11537(Internet 2), AS313=
0(RGnet, LLC) and AS25973(Mzima >Networks, Inc). I'm not sure if my info is=
correct. Does SIX own its own ASN other than the three above?
Sorry for the misfire on my last email. The 206.81.80.0/23 network is assi=
gned to the SIX from ARIN. In general, we don't want people to announce t=
hat space to the DFZ, so the three providers listed above are not filtering=
their announcements properly. It is, as others have said, a good idea to =
announce the exchange block to your customers, but not out to the DFZ.
Regards,
Mike
