On Fri, 28 Feb 2003, Steven M. Bellovin wrote: :But -- given things like the AS7007 incident, and given the possibility :-- probability? -- that it can happen again, can we afford to not do :sBGP? My own opinion is that sophisticated routing attacks are the :single biggest threat to the Internet. Without sliding into a discussion about what our worst imaginable attack would be, how are they more of a threat than a worm that saturates links? I am interested in how you measure the threat of attacks against routing protocols against that of something like slammer, as I would think that routing problems would limit their own propagation much faster than say, the way slammer slowed itself down by saturating links. I am taking sophisticated routing attacks to mean specific protocol exploitation, instead of attacks on the devices themselves. I would even suspect that it is not possible for routing information to be scrambled in any widely propagated and irrepairable way, for similar reasons to why it can't be kept straight without constant updates. That is, the routes confusion will limit it's own propagation precisely because it may no longer know how to propagate itself. Or rather, the more valid paths valid routing information has, the more likely it will spread, no? I wonder how you could test that. Thanks, -- batz