BGPMON Alert Questions

Andrew (Andy) Ashley andrew.a at
Wed Apr 2 19:33:33 UTC 2014

Hi All,

I am a network admin for Aware Corporation AS18356 (Thailand), as
mentioned in the alert.
We operate a BGPMon PeerMon node on our network, which peers with the
BGPMon service as a collector.

It is likely that AS4761 (INDOSAT) has somehow managed to hijack these
prefixes and CAT (Communications Authority of Thailand AS4651) is not
filtering them, 
hence they are announced to us and are triggering these BGPMon alerts.

I have had several mails to our NOC about this already and have responded
directly to those.
I suggest contacting Indosat directly to get this resolved.
AS18356 is a stub AS, so we are not actually advertising these learned
hijacked prefixes to anyone but BGPMon for data collection purposes.



Andrew Ashley

Office: +27 21 673 6841
E-mail: andrew.a at

On 2014/04/02, 21:05, "Vlade Ristevski" <vristevs at> wrote:

>I just got the same alert for one of my prefixes one minute ago.
>On 4/2/2014 2:59 PM, Frank Bulk wrote:
>> I received a similar notification about one of our prefixes also a few
>> minutes ago.  I couldn't find a looking glass for AS4761 or AS4651.
>>But I
>> also couldn't hit the websites for either AS, either.
>> Frank
>> -----Original Message-----
>> From: Joseph Jenkins [mailto:joe at]
>> Sent: Wednesday, April 02, 2014 1:52 PM
>> To: nanog at
>> Subject: BGPMON Alert Questions
>> So I setup BGPMON for my prefixes and got an alert about someone in
>> Thailand announcing my prefix.  Everything looks fine to me and I've
>> checked a bunch of different Looking Glasses and everything announcing
>> correctly.
>> I am assuming I should be contacting the provider about their
>> misconfiguration and announcing my prefixes and get them to fix it.  Any
>> other recommendations?
>> Is there a way I can verify what they are announcing just to make sure
>> are still doing it?
>> Here is the alert for reference:
>> Your prefix:
>> Update time:          2014-04-02 18:26 (UTC)
>> Detected by #peers:   2
>> Detected prefix:
>> Announced by:         AS4761 (INDOSAT-INP-AP INDOSAT Internet Network
>> Provider,ID)
>> Upstream AS:          AS4651 (THAI-GATEWAY The Communications Authority
>> Thailand(CAT),TH)
>> ASpath:               18356 9931 4651 4761
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