On Sun, Apr 12, 2020 at 08:39:58PM +0200, Robert Raszuk wrote:
> Would anyone be able to explain the below phenomenon?
> 
> RPKI Origin validation marks net 45.227.254.0/24 as INVALID as it expects
> it to be originated by ASN: 395978

If you look at https://stat.ripe.net/45.227.254.0%2F24#tabId=routing you
can see that the prefix is only seen by 72% of the RIPE RIS collectors,
this is a very low score, I'd consider this a problematic network
outage. If you'd have internet access users serviced out of the block it
probably would mean many websites don't work, or don't work well.

In the 'Routing History' widget we can see:

    May 2018 - Jul 2018 - AS 395978 
               Aug 2018 - AS 62088
    Oct 2018 - Mar 2019 - AS 42260
    Feb 2019 - Mar 2020 - AS 51852

I guess early someone deemed AS 395978 deemed to be the right origin ASN
and create RPKI ROAs, but subsequently didn't update these RPKI ROAs to
the new ASNs as the space moved from lessee to lessee. I suspect IP
address leasing is in play because the announcement periods don't seem
to overlap, suggesting there might have been coordination between
previous and next Origin ASN.

Since the ROA still exists, whoever created the ROA (to authorize
395978) still is in authority, so from an operational perspective it is
incumbent on that entity to correct the RPKI information. If the space
had been transferred from one LIR to another LIR the 'offending' ROA
would've been deleted in that transfer process.

> But it comes from  51852 which according to ipinfo or bgpview is
> legitimate ASN:
> 
> https://ipinfo.io/AS51852/45.227.254.0/24
> https://bgpview.io/prefix/45.227.254.0/24

I am not sure in what way you are reading the data, the information
displayed here doesn't weigh in on legitimacy. Both websites are
frontends to public whois data, they shows the prefix is suballocated to
'Xwin universal ltd', but the originating ASN is 'Private Layer INC'.

> As I see similar discrepancies in many global networks I would like to
> ask who to trust ? If RPKI data is not valid then I think we have a
> real problem.

I am not sure it is about trust. I trust the system works as designed,
which means there is potential for human error in the ROA creation
process. In this sense IRR, DNSSEC, and RPKI have some similarities -
they all potentially set a user up for failure.

Operators deploying OV have to the balance of inconvenience for entities
who misconfigured their ROA against the consequences of accepting BGP
misconfigurations or hijacks of prefixes which could've been prevented
had ROAs been honored.

An operator should notify its customers who are announcing RPKI invalids
before deploying Origin Validation with 'invalid == reject' policies on
the EBGP edge. This way the alert notification about the ROA
misconfiguration follows contractually established inter-organisation
communication channels. Sometimes that mechanism works well!

Another theory is that some (a lot?) of the RPKI Invalids that exist in
the default-free zone in a steady state are not really in use, just
'parked'. Folk wisdom suggests if you don't announce all your prefixes
in the DFZ, malicious actors tend to notice and start using the space in
your stead. Because of this (and other reasons) we can't really know
what IP address space is actually in use or not.

Traffic studies done by some network operators in the months prior to
deploying RPKI OV commonly show very little or no traffic destined for
RPKI Invalids. In these studies it is important to separate RPKI
invalids that become 'unreachable', and traffic for IPs covered by RPKI
invalids which are covered by a less specific not-found/valid
announcement. 
https://mailman.nanog.org/pipermail/nanog/2019-February/099522.html

Back to the prefix at hand, I believe this to be the party in charge of
the RPKI ROA:

    $ whois 45.227.252.0/22 | grep @ | sort -u
    e-mail:      n...@flyservers.com

One could reach out to the operator and ask them?

Kind regards,

Job

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