Hi there, Perhaps this would be easier and help you out:
http://bgp.he.net/AS3701#_graph4 Cheers, Hamish On Tue, Dec 9, 2014 at 12:48 PM, Reza Motamedi <[email protected]> wrote: > Hello NANOG, > > I’m a researcher and I was trying to understand the data I collected from > some BGP Looking Glasses. Basically, I was hoping to see if BGP records can > tell me where my university’s provider (AS3701) is peering with its > providers. I issued two BGP queries to Level3’s LGs, one in Seattle and one > in Amsterdam for my school’s prefix. My strong guess was that our provider > (AS3701) peers with Level3 in Seattle. I was hoping to conclude something > like this: if the peering occurs in Seattle, the Seattle LG should reveal > it, but Amsterdam should not. > > AS3701 is Nero (Network for Education and Research in Oregon) which I > assume is a small regional AS. I don't think Nero peers with Level3 in > Amsterdam, however, I get this AS for my next hop even when I issue the > command from Amsterdam. On the other hand “car1.Sacramento1” suggests that > the peering happens in Sacramento. > > This result makes me think what I get is from a combination of iBGP and > eBGP, which is also apparent from “Internal/External” keywords in the data. > My main issue is that the keywords are not always available. In some other > LG I just get a next hop IP and an AS path. How can I make sure that the > peering information comes from an eBGP peering? I think the next hop IP > might be the answer, right? > > I included the results of the command for both LGs here, hopefully somebody > could explain to me > > ------------------------------------------------- > > Route results for 128.223.0.0/16 from Amsterdam, Netherlands > > BGP routing table entry for 128.223.0.0/16 > > Paths: (2 available, best #1) > > 3701 3582 > > AS-path translation: { OREGONUNIV UONET } > > car1.Sacramento1 (metric 58341) > > Origin IGP, metric 0, localpref 100, valid, internal, best > > Community: North_America Lclprf_100 Level3_Customer United_States > Sacramento > > Originator: car1.Sacramento1 > > 3701 3582 > > AS-path translation: { OREGONUNIV UONET } > > car1.Sacramento1 (metric 58341) > > Origin IGP, metric 0, localpref 100, valid, internal > > Community: North_America Lclprf_100 Level3_Customer United_States > Sacramento > > Originator: car1.Sacramento1 > > ------------------------------------------------- > > Route results for 128.223.6.81/16 from Seattle, WA > > BGP routing table entry for 128.223.0.0/16 > > Paths: (4 available, best #3) > > 3701 3582 > > AS-path translation: { OREGONUNIV UONET } > > 4.53.150.46 from 4.53.150.46 (ptck-core1-gw.nero.net) > > Origin IGP, localpref 90, valid, external > > Community: North_America Lclprf_90 Level3_Customer United_States Seattle > Level3:11847 > > 3701 3582, (received-only) > > AS-path translation: { OREGONUNIV UONET } > > 4.53.150.46 from 4.53.150.46 (ptck-core1-gw.nero.net) > > Origin IGP, localpref 100, valid, external > > Community: Level3:90 > > 3701 3582 > > AS-path translation: { OREGONUNIV UONET } > > car1.Sacramento1 (metric 34363) > > Origin IGP, metric 0, localpref 100, valid, internal, best > > Community: North_America Lclprf_100 Level3_Customer United_States > Sacramento > > Originator: car1.Sacramento1 > > 3701 3582 > > AS-path translation: { OREGONUNIV UONET } > > car1.Sacramento1 (metric 34363) > > Origin IGP, metric 0, localpref 100, valid, internal > > Community: North_America Lclprf_100 Level3_Customer United_States > Sacramento > > Originator: car1.Sacramento1 > > > Best Regards > Reza Motamedi (R.M) > Graduate Research Fellow > Computer and Information Science > University of Oregon >
