[atlas] AS number in traceroute data

On Mon, 29 Apr 2013, Robert Kisteleki wrote:

> On 2013.04.26. 12:14, Pavel Veselovskiy wrote:
>> Hello,
>>
>> Is it possible to perform RIPE Atlas measurements with a key "-A" that
>> shows the number of autonomous systems?
>>
>> -
>> Kind Regards,
>> Pavel Veselovskiy,
>> Samara State Aerospace University
>
> Hello,
>
> No, there's no support for this on the probes. It'd be pretty expensive for
> to do this on the fly, as it involves a lookup (into BGP or IRRs) for
> virtually every packet received.
>
> But it would be possible to annotate the results in some way, when storing
> them or when you access them. Is this something that would be interesting
> for others too?
>
> Regards,
> Robert
>
>
> PS: of course the task itself is far from trivial. Trying it out on a random
> Linux box gave me the "wrong AS" for almost half of the cases. I'm sure
> there could be extensive discussion around how to Do This Right in the first
> place :)
>
>

Doesn't sound so hard to implement, could be done via a DNS lookup.
For instance if you want to check what is the AS for IP 1.2.3.4, you do a 
DNS lookup for 4.3.2.1.whatismyas.example.com and get the result.
This will move the complexity away from the tiny probe and to a place 
where some complexity wouldn't be a problem (i.e. a DNS server).