Thus spake "Scott Michel" <scottm@xxxxxxxxxxx> > 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. The Mbone and 6bone are different beasts, as they're about tunneling traffic from capable hosts across an incapable core. In the case of an identity layer between IP and TCP, we would need to be backwards-compatible with non-capable hosts and applications (not just non-capable routers) and so tunnels don't seem a workable solution. > > 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. Ditto... > > 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. All too true. We do, however, know many of the IETF's needs in the identifier/locator arena, e.g. for Mobile IP and IPv4/6 multihoming. That may be a good starting point to determine what, if any, additional requirements DARPA has. S Stephen Sprunk "Stupid people surround themselves with smart CCIE #3723 people. Smart people surround themselves with K5SSS smart people who disagree with them." --Aaron Sorkin