Hi nusenu,  

Please note that the RPKI Validator BGP Preview only shows announcements that 
are “widely seen”, which in this case 5 peers or more. Anything lower than that 
will not simply show up in the list, however it may still be listed in the dump 
file Rene linked to.

Cheers,

—Alex

> On 27 Sep 2018, at 03:07, Rene Wilhelm <[email protected]> wrote:
> 
> Hi,
> 
> On 9/27/18 1:11 AM, nusenu wrote:
>> Hi,
>> I came across this particular prefix when going through big RPKI unreachable 
>> blocks.
>> prefix-routing-consistency [1] says: current origin is AS2200
>> prefix-overview [2] says: current origin is AS1942  (nlnog's LG agrees)
>> routing-history [3] says it was announced by AS220 until 2017-06-10 and is 
>> currently announced by AS1942
>> RPKI validator's BGP Preview (using RIS): says it is announced by AS1942 and 
>> is therefore invalid
>> (ROA authorizes AS2200 - not AS1942)
>> So why does [1] say this prefix is announced by AS2200? maybe it is 
>> announced by both?
> 
> 
> I do not know what is announced, but RIS observes the prefix with both 
> origins. As the looking-glass widget states:
> 
> "19 RRCs see 202 peers announcing 147.171.0.0/16 originated by 2 ASNs"
> 
> https://stat.ripe.net/widget/looking-glass#w.resource=147.171.0.0%2F16
> 
> Actually, it is just one single peer on collector rrc04 (Geneva) which sees 
> AS2200 as origin; that's why prefix-overview and routing-history
> do not show the info by default. You have to deselect 'Exclude low
> visibiliy' (prefix-overview) and 'No low visibility' (routing-history) 
> options in the widgets to see it.
> 
> RPKI validator's BGP Preview might be using similar logic.
> The latest RIS dump, http://ris.ripe.net/dumps/riswhoisdump.IPv4.gz
> lists 147.171.0.0/16 with both AS1942 (203 peers) and AS2200 (1 peer)
> as origin.
> 
> prefix-routing-consistency widget appears to indeed have problems;
> at least in this case. It only shows a result for the route observed
> by the lowest amount of peers.
> 
> 
> -- Rene
> 
> 
> 
> 
> 
>> btw: AS2200 and AS1942 have the same owner and AS2200 appears to be
>> the only upstream of AS1942.
>> [1] 
>> https://stat.ripe.net/widget/prefix-routing-consistency#w.resource=147.171.0.0%2F16
>> [2] https://stat.ripe.net/widget/prefix-overview#w.resource=147.171.0.0%2F16
>> [3] https://stat.ripe.net/widget/routing-history#w.resource=147.171.0.0%2F16


Reply via email to