[mat-wg] Requested Feature: RIS Prefixes

Dear colleagues,

In May this year there was a feature request from Job Snijders to have
RIPEstat provide transitted prefixes for an ASN. See [0] for more details.

Over the summer we worked on this feature. As a result we now have a new
data call in the RIPEstat API called RIS Prefixes. This data call
reports the prefixes for a given ASN that are seen on the AS paths
between the origin and RIS. You can see an example using the RIPE NCC's
ASN (AS3333):

http://stat.ripe.net/data/ris-prefixes/data.json?resource=AS3333&list_prefixes=true

The data call supports the additional parameter of tailoring the output
to your needs. See [1] for more details.

The data is based on data collected by the RIPE NCC's RIS network (see
[2]), and the output therefore reflects the perspective of RIS.

Important to interpreting the data correctly is the definition of a
transit: for this dataset, a transit is defined as any ASN appearing on
the AS path for a route that is not the origin. We understand that the
term “transit" can also imply the business relationship between
networks, which would provide a list of prefixes that could be referred
to as prefixes in the customer cone of a network. At this point in time,
the customer cone itself cannot be extracted from the RIS data in a way
that is exact and reliable. The RIS Prefixes data call provides a
SUPERSET of prefixes considered the customer cone.

During the coming months we will further investigate the possibilities
of determining customer prefixes with RIS/RIPEstat. Meanwhile, we
welcome suggestions from the community for approaches to solve this issue.

We look forward to hearing from you,

Christian Teuschel & Romeo Zwart
RIPE NCC

[0] https://www.ripe.net/ripe/mail/archives/mat-wg/2015-May/000588.html
[1] https://stat.ripe.net/docs/data_api#RISPrefixes
[2] https://www.ripe.net/ris