CAIDA's AS-rank project

Richard Barnes richard.barnes at
Fri Sep 7 22:51:34 UTC 2012

No IPv6?

On Thu, Sep 6, 2012 at 6:46 PM, Matthew Luckie <mjl at> wrote:
> Hello,
> We have been working on refreshing the data and algorithms behind CAIDA's
> as-rank project.  We have published AS-relationships and AS-rankings
> computed for June 2012.  We are currently seeking further validation of our
> rankings and relationship inferences.
> The core of the algorithm is the inference of business relationships. Over
> the past two years we have received a significant amount of ground truth
> from operators through the corrections facility provided within AS-rank: in
> particular we obtained >1200 p2p relationships as a result of our previous
> algorithm that assigned many more customer/provider (c2p) relationships than
> ASes had in reality.  Our intuition is that network owners are a lot more
> concerned when we infer a provider relationship that is actually a peer
> relationship, but are less motivated to validate other inferences.
> We have validated our algorithm against available ground truth and find our
> relationship inferences have a 99.1% positive predictive value (PPV) for c2p
> and 94.7% for p2p for the validation data we have available. Because
> customer cone computation depends on the accuracy of our c2p inferences, we
> are reasonably confident in our computed rankings.
> We are now soliciting further feedback in any shape and form offered. The
> as-rank website provides the ability for operators to submit corrections
> through the right-most "corrections" button on an individual ASes
> information page, and relationships ground-truth is solicited through that
> channel, if at all possible.  Other feedback, on or off-list, would also be
> appreciated.
> If you are curious as to why a particular relationship was inferred, please
> get in contact with me.  Some ASes have advised of a particular business
> relationship in the past, but when I drill down into the data it turns out
> they have a misconfiguration and are leaking routes to a peer.  At a
> minimum, this might be a useful sanity check for some ASes who may be
> providing free transit without realising it.  In the future, we plan to
> annotate each relationship with examples as to why it was inferred the way
> it was, but we have not yet got that far yet.
> Thanks,
> Matthew Luckie

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