Internet Exchange Point(IXP) questions

Fri Feb 18 21:36:28 UTC 2011

On Fri, Feb 18, 2011 at 4:29 PM, Leo Bicknell <bicknell at ufp.org> wrote:
> In a message written on Fri, Feb 18, 2011 at 02:34:21PM -0500, Christopher Morrow wrote:
>> why is it a good idea to send this to your customers? the next-hop
>> info is surely only useful to your local network? done right it's even
>> only relevant to the IX connected router, right? it seems wholely
>> unusful to your customers. (to me at least)
>
> If by "done right" you mean perhaps a feature like returning ICMP's from
> a loopback IP rather than the interface IP, there are two issues with

sorry, I was only talking|thinking about routing bits, I missed your
point about people being able to ping an IX interface... I'd submit
that in many networks the path to the nexthop may be a vastly
different one than the path to 'the broken thing' through the
isp/ixp/isp set of routers.

I meant: "Is the nexthop in your (the ixp connected isp) network the
IXP interface IP, or the loopback of your IXP connected router?"

'Done right' (I agree that this is an individual perspective) here
meant, to me, that the IXP prefix wasn't necessary in the IXP
connected ISP's network, reset to loopback in ibgp policy and never
send the IXP prefix (connected route) off the IXP connected router.

leaking the IX prefix to customers, to me, seems like a recipe for
much wider/unintended leakage :(