Dan McDonald wrote: >> Your attacker is often a legitimate user of the link.
James Kempf wrote: > Right, that's the point I was trying to bring up in my response to Alex. > Just because someone has undergone AAA successfully doesn't mean that > they won't disrupt the link. I completely agree. Additionally, I'd like to see an infrastructureless solution to be used anywhere possible. Why? Basically because an infrastructureless solution means that we can make it to work with zero configuration, while any infrastructure necessarily needs that either the initial credentials must be configured or that new nodes must learn the credentials of the infrastructure through "leap of faith". Dan McDonald wrote: >> In a perfect world, ND would allow a host to only do host-type things, >> and then only on behalf of the host itself. >> ... >> Solve the aforementioned Jeff Schiller problem, and you probably can >> secure ND. If you can't, all such solutions will just limit your >> troublemakers to who is allowed on the LAN. ... James Kempf wrote: > What we were trying to do in the ABK draft was provide a way that a node > on the link could determine definitively that a particular ND/RA message > came from the node/router possessing that identity. There main issue is > some way to establish the right of the node to possess that identity > beforehand, and we included sketches of a couple ways that seem > consistent with current practice. We probably need to flesh these out > some. > > That said, ABK is a new an largely unknown technology. In the security > area, old and well trusted technologies are often easier to make work, > because the holes are well known and can be patched around. So a > solution based on IPsec, should it be possible to make it work and prove > secure, would certainly be of interest. Already a year ago I tried to point out that CGA can be used to solve the ND security problem. Since CGA is able to securely bind a public key to a interface ID, you can use CGA to verify that the right party "speaks for" the interface ID. That seems to be sufficient to solve ND. However, it doesn't help much with router discovery. Personally, I think that ABK might have great potential for router discovery, since ABK can to convert even network prefixes into public keys. Now, if we just could figure out how we could use ABK to somehow express trust relationships between more covering prefixes (e.g. 3ff0::/16) and subprefixes (e.g. 3ff0:1::/20), then we would have something... Back then I also wrote an I-D, which describes one method how CGA can be used for ND. For various reasons that I-D never got published, but it has been available and is still available at http://www.tml.hut.fi/~pnr/publications/draft-nikander-ipng-pbk-addresses-00.txt The basic ideas are also described in Pekka Nikander, "Denial-of-Service, Address Ownership, and Early Authentication in the IPv6 World", presented at Cambridge Security Protocols Workshop 2001, April 25-27, 2001, Cambridge University. To be published in the workshop proceedings at the LNCS series. A pre-publication version of the paper is available at http://www.tml.hut.fi/~pnr/publications/cam2001.pdf --Pekka Nikander -------------------------------------------------------------------- IETF IPng Working Group Mailing List IPng Home Page: http://playground.sun.com/ipng FTP archive: ftp://playground.sun.com/pub/ipng Direct all administrative requests to [EMAIL PROTECTED] --------------------------------------------------------------------
