> >> draft-hui-6lowpan-hc-00 now allows us to do everything which the >> mesh-header does, and more. Sending packets to a global IPv6 node >> using the mesh header now requires both the mesh-header, plus an L3 >> destination address. Quite inefficient. Plus there is again the >> issue of implementation, testing, and interop along with a >> confusing spec where routing src/dst can be carried both in lowpan >> and IPv6 headers.. This situation is similar to that of HC1 and HC. >> The mesh-header will slowly depreciate anyways, especially with ROLL >> activity, and for interop reasons between vendors. Let's depreciate >> it now and stop the annoying mesh-under vs. route-over confusion. > >I'm all for simplicity - it's quite significant when we're dealing >with resource-constrained devices that are hard to debug. Again, I >think we should be more explicit about routing vs. forwarding. The >mesh header allows L2 forwarding, but there's no reason why you >couldn't combine that with L3 routing. Then there's the L3 vs. L2 >routing debate and, if it hasn't been obvious already, I'm all for an >L3 routing approach. I wouldn't want us to relive the days of LAN >emulation in dynamic, multihop networks, especially those that are >resource-constrained. [Pascal]
That's how I see it too and this echoes Stephen's question about forwarding compressed packets. A simple way to decide whether to terminate 6LoWPAN or to forward a 6LoWPAN packet still compressed is to have the information in the header. For instance, the routing computes which sink is the best exit point to leave the 6LoWPAN network towards the final destination. That sink should become the place where 6LoWPAN is terminated and fragments are recomposed. The "mesh" header becomes a routing header that forces all the packets to be routed via the sink. Forwarding happens along a graph towards that sink, and 6LoWPAN is not finished until the next hop in the routing header is reached. On the way back, The routing header indicates the last router (FFD) that serves the final destination if that one does not route. Makes sense? _______________________________________________ 6lowpan mailing list [email protected] https://www.ietf.org/mailman/listinfo/6lowpan
