On Tue, Mar 8, 2022 at 3:33 PM Robert Raszuk <rob...@raszuk.net> wrote:
> > Right - but IMO route leaking can happen both in the Internet or in > customer <- via IXP -> content provider interconnects. > > And in the latter case - especially for those with open peering policy - > often going via RS. After all this is how route servers are mainly used > today :) So both sides will be peering to IXP RS while IXP RS will (in most > cases) not appear in the AS_PATH. > > > sure! that was my re-wording of sriram's question, effectively. (or I think that was the re-wording!) > > > On Tue, Mar 8, 2022 at 9:26 PM Christopher Morrow < > christopher.mor...@gmail.com> wrote: > >> >> >> On Tue, Mar 8, 2022 at 3:15 PM Robert Raszuk <rob...@raszuk.net> wrote: >> >>> Well I think the answer is - it depends. >>> >>> First IXP fabric can be used as pure L3 share LAN or can be used (and it >>> is often the case) as a p2p emulated VLAN over such L3 shared LAN. >>> >>> Now if this is L3 shared LAN still customer and ISP may peer directly >>> and no third party traffic would be accepted at either end. >>> >>> If we talk about emulating L2 IXP fabric becomes just an emulated >>> circuit and from the perspective of routing it a p2p interface. >>> >>> Sure the other aspects of the IXP quality, port monitoring, >>> oversubscription etc... always will apply but there are ways to mitigate or >>> handle those in real IXPs. >>> >>> >> I don't dispute your content here, except that Sriram's question was >> about seeing 'customer routes via the RS'... which I think would obviate >> the emulation examples you provided. >> (well in a bunch of cases it would, you COULD hook up some tomfoolery to >> get this to work, but... that sounds complex and prone to disaster) >> >> >>> Best, >>> R. >>> >>> >>> >>> >>> >>> >>> >>> >>> On Tue, Mar 8, 2022 at 9:05 PM Christopher Morrow < >>> christopher.mor...@gmail.com> wrote: >>> >>>> >>>> >>>> On Tue, Mar 8, 2022 at 2:36 PM Sriram, Kotikalapudi (Fed) >>>> <kotikalapudi.sriram=40nist....@dmarc.ietf.org> wrote: >>>> >>>>> This question has relevance to the ASPA method for route leak >>>>> detection. >>>>> >>>>> Is it possible that an ISP AS A peers with a customer AS C via a >>>>> non-transparent IXP AS B? >>>>> IOW, the AS path in routes propagated by the ISP A for customer C's >>>>> prefixes looks like this: A B C. >>>>> I.e., can the AS of a non-transparent IXP/RS appear in an AS path in >>>>> the middle between an ISP and its customer? >>>>> >>>>> >>>> it seems unlikely to me that an ISP would pick up a 'customer' (someone >>>> that pays them to transport packets) at an IXP fabric. >>>> Might it happen? sure? is it messy? yes! >>>> >>>> 1) that's probably a shared port >>>> 2) there are other folk feeding routes and packets into the mix >>>> 3) how many came through the 'customer' port (which you can't really >>>> know easily) vs other participants on the ix >>>> 4) what capacity planning could the 'customer' do here? (none, >>>> basically with respect to the remote ISP port) >>>> >>>> Your question might work also as: >>>> "ISP A has a customer C on a direct link in location Y. >>>> ISP A is present at IXP-Z, so is customer C, though they do not >>>> bilaterally peer (not do they interconnect at the IXP). >>>> ISP A can still see Customer C's routes through the IXP-Z Route >>>> Server." >>>> >>>> that seems plausible, but not a desired outcome for the ISP :) since >>>> they will be unlikely to collect pesos for the traffic >>>> which MAY pass across that interconnect. >>>> >>>> _______________________________________________ >>>> GROW mailing list >>>> GROW@ietf.org >>>> https://www.ietf.org/mailman/listinfo/grow >>>> >>>
_______________________________________________ GROW mailing list GROW@ietf.org https://www.ietf.org/mailman/listinfo/grow
