On Tue, Mar 16, 2004 at 07:09:12PM -0600, Stephen Sprunk wrote: > When you add in the (assumed) requirements of backwards compatibility with > existing routers and hosts that don't implement a proposed extension, it > gets messy real quick. The immediate handwave would be "Tunnel it." I'm not denigrating backwards compatibility, but a lot of good work has relied on tunneling in the past, e.g., Mbone and v6-v4. I'm currently waiting with baited breath the day that service providers provide v6-to-v4 as the special case to v4-only hosts. > HIP is a good start, but it's still only a BOF and the involvement is > nowhere near what one would expect for (IMHO) the most significant IETF > project since IPv6. Must find more copious free time. Must find more copious free time. > While that's certainly interesting in its own right, what I think DARPA (and > the IETF) is looking for is something between the network and transport > layers, not something above transport. You never know until you submit a proposal what DARPA **really** wants even after you get through the program-speak. FLAPPS got funded for a while under the Fault Tolerant Networks program, as did a lot of other research. Might be that there are multiple shim layers between network and transport, transport and application. That said, a lot of things can be solved in the application layer (or adding thin layers underneath the app layer) because adding them to the network and transport layer is less tractable. A good example is multicast -- it works well and fits into the network layer but the problems with routing protocols to get the distribution tree built turns out to be a long IETF standards process exercise. Application-layer mcast seems to be more of a winner than network-layer (just my perception, you may now fire at will.) In any case, it's fuel for interesting discussions. -scooter