A New Internet-Draft is available from the on-line Internet-Drafts directories.
Title : Avoiding un-trusted AS thru inter-AS TE-LSPs constructed using Clipping
Author(s) : Shankar Raman
Balaji Venkat Venkataswami
Gaurav Raina
Bhargav Bhikkaji
Filename : draft-balaji-mpls-inter-as-policy-based-te-sec-00.txt
Pages : 11
Date : 2012-08-01
Abstract:
For a short time sometime in the recent past , internet traffic sent
between a well known site and subscribers to an internet service
provider A passed through hardware belonging to a Telecom provider B
other than the ISP A to which the customers were attached before
reaching its final destination. Telecom Provider B was found to be
many AS hops away from the well known site and ISP A. It was assumed
that this was an an innocent routing error (which is the most likely
explanation for the highly circuitous route that the traffic was
taking), but it was troubling nonetheless. During a window that
lasted 30 minutes to an hour, all unencrypted traffic passing between
the victimised ISP's customers and the well known site might have
been open to monitoring. Though there was no evidence any data was in
fact snarfed, but it was felt that the potential for that is
certainly there because the hardware belonged to the untrusted
Telecom provider B.
Many such incidents have occurred in the past where the traffic has
been diverted through such providers that either erroneously have let
loose BGP routes or otherwise. At least one of those incidents was
the result of erroneous BGP, or Border Gateway Protocol, routes that
were quickly corrected. The above is a hypothetical headline that
might occur in the near future if the BGP protocol is subject to such
circuitous routing attacks either by mis-configuration or through
purposeful intent. This is primarily owing to the fact that the BGP
protocol accepts updates from providers and there exists no mechanism
to figure out whether the updates for prefixes received was due to
mal-intent, mis-configuration or indeed correct configuration. So
there is a big blind spot that will have to be rectified. Doing the
rectification through BGP would only complicate matters more.
The proposal in the scheme in this draft, warrants the use of MPLS-
based inter-AS Traffic Engineered Label Switched Paths that are
constructed out of a derived inter-AS topology that help to impose
policy decisions that for eg, obviate or prevent such LSPs from
actually going through certain specific AS or set of ASes. Using
methods like Graph construction from AS-PATH-INFO data and methods
like policy based clipping of edges and nodes from such a inter-AS
topology, the solution is made simple. The use of PCE (Path
Computation Elements) is advised to compute such inter-AS paths that
avoid ASes. Regular routing would have followed BGP updates and
regular IP based forwarding. Using the TE-LSPs we can in fact set out
the explicit route from AS to AS from the head-end to the tail-end
avoiding specific set of ASes which dictated by policy have to be
avoided.
The IETF datatracker status page for this draft is:
https://datatracker.ietf.org/doc/draft-balaji-mpls-inter-as-policy-based-te-sec
There's also a htmlized version available at:
http://tools.ietf.org/html/draft-balaji-mpls-inter-as-policy-based-te-sec-00
Internet-Drafts are also available by anonymous FTP at:
ftp://ftp.ietf.org/internet-drafts/
_______________________________________________
I-D-Announce mailing list
I-D-Announce@ietf.org
https://www.ietf.org/mailman/listinfo/i-d-announce
Internet-Draft directories: http://www.ietf.org/shadow.html
or ftp://ftp.ietf.org/ietf/1shadow-sites.txt
