How Not to Multihome

Tue Oct 9 18:01:40 UTC 2007

On Oct 9, 2007, at 1:53 PM, Valdis.Kletnieks at vt.edu wrote:

>> There are currently ~1500 prefixes with inconsistent origin AS.
>> These are trivially identifiable:
>>
>>    <http://www.cymru.com/BGP/incon_asn_list.html>
>>
>> Some of them are obvious mistakes (I doubt HKSuper is supposed to
>> originate 4/8).  But many of them are not, and the Internet works
>> just fine.
>
> And as Justin said, some sizable fraction of those 1500 prefixes are
> quite possibly *appearing* to Work Just Fine currently, but if  
> something
> breaks, that will be 1500 NOC monkeys facing some difficult-to-debug
> routing issues....

Considering the number of inconsistently originated prefixes has been  
non-trivial for at least a decade, I have trouble believing this is a  
huge threat to the internet.  Or even those 1500 NOC monkeys.  (And  
wouldn't it be 3K - at least 2 ASNs per prefix? :)

-- 
TTFN,
patrick