thanks, sure, this subject is also in that other in-submission paper. in a nutshell: almost all greedy paths are policy-compliant paths! BUT: if we want to *actively* manage mapping as a function of policies, then it's currently impossible, although we have some ideas on how to achieve this.. -- dima. http://www.caida.org/~dima/
On Monday, September 13, 2010 3:24 PM, Tony Li wrote: > Hi Dmitri, > > Might I suggest that a discussion of transit policies might also be in order? > > Thanks, > Tony > > > On Sep 13, 2010, at 3:08 PM, Dmitri Krioukov wrote: > >> thanks much for you comments! indeed, topology dynamics is >> concern #1 in geometric routing. that's why we considered both >> short- and long-term dynamics, all in the paper. we emulate the >> former (by killing a percentage of links and nodes) and >> replayed the latter using the measurable history of internet >> evolution over the past few years with ASs and AS connections >> appearing, disappearing, etc., and the results are still very >> good, pretty much the same as for the static case. amazing, >> isn't it? i know it's hard to believe, and even we can't stop being >> surprised how well it works. we have another paper in submission, >> where we take space to explain why it works so well, and where >> we discuss some aspects of what it would take to implement >> and use this stuff in practice. >> -- >> dima. >> http://www.caida.org/~dima/ >> >> On Friday, September 10, 2010 4:29 PM, Sampo Syreeni wrote: >> >>> On 2010-09-09, Dmitri Krioukov wrote: >>> >>>> marshall, thanks for posting it here. i also thinks it's relevant :) >>> >>> Thanks from me too, and it's certainly relevant. Still, it might not be >>> as good an idea as it sells itself as. >>> >>> Geometric routing ideas have been around for quite a while now. They >>> certainly do this sort of thing within manets right now, because of the >>> spatial nature of a cloud of terminals/sensors. So in certain ways the >>> idea works well indeed. >>> >>> I'd be the first to say that geometric routing is a swell and elegant >>> idea. Yet, it tends to have some inherent problems in the wired setting >>> where a) the topology and the geometry of the network isn't as static as >>> a cloud of 3D sensors would see, b) where we have to have static contact >>> points like DNS fully available at more or less fixed destination >>> addresses all of the time, to map from points of interest to >>> topological/geometrical addresses/locations, c) any static mapping like >>> the one proposed in the paper could *severely* undercut routing >>> efficiency as soon as someboby built a new undersea cable, which of >>> course severely changes the routing landscape in one fell swoop, and d) >>> when we then probably would go with an adaptive routing protocol, there >>> is a serious problem with asymmetric paths. That final problem doesn't >>> plague just Euclidean distance measures, but all of the metric ones as >>> well, including the hyperbolic. >>> >>> As regards an adaptive geometric routing protocol, IRTF's ALTO group has >>> charted this stuff quite extensively already in the context of routing >>> within overlay networks. I suggest everybody look into that body if they >>> haven't already, if interested in geometric routing. >>> >>> In my opinion, this particular article is a nice touch onto how best >>> parametrize network distance. Based on the article and the references, a >>> hyperbolic space might well provide us with a better parametrization of >>> distance in a scale-free network within the geometric routing paradigm. >>> But it won't solve the more fundamental problems which have stopped us >>> from adopting geometric routing in the past. >>> >>> I'd say this body of work is a building block for further research, more >>> than the showstopper it'd like us to see itself as. >>> -- >>> Sampo Syreeni, aka decoy - [email protected], http://decoy.iki.fi/front >>> +358-50-5756111, 025E D175 ABE5 027C 9494 EEB0 E090 8BA9 0509 85C2 >> >> _______________________________________________ >> rrg mailing list >> [email protected] >> http://www.irtf.org/mailman/listinfo/rrg _______________________________________________ rrg mailing list [email protected] http://www.irtf.org/mailman/listinfo/rrg
