Hi Phil and Carles,
On 5/28/08 1:38 AM, "Philip Levis" <[EMAIL PROTECTED]> wrote: > On May 27, 2008, at 2:29 AM, Carles Gomez Montenegro wrote: >> >> At least, there are the following items listed in the routing >> requirements >> draft (http://tools.ietf.org/id/draft-dokaspar-6lowpan-routreq-05.txt) >> that route-over approach cannot provide or would provide only in a >> limited >> way: > > I disagree wholeheartedly. So do I. I think there is a big confusion here > between a protocol specification and a protocol implementation. > > These are all arguments for cross-layer design, that tightly > integrating routing and the link layer will lead to a better solution. > Practice has shown us otherwise; Indeed, "practice" being "The Internet". only by clearly separating concerns > do you give a protocol the flexibility needed to evolve over time. > What happens when a new low power link layer emerges? Having N > different solutions, each with their own details, which somehow need > to be made to work well together, seems like a path of brittle and > difficult to manage networks. Switches are good, to a point; there's a > reason you have routers. > > The purpose of a protocol specification, IMO, is to specify what is > needed for interoperability; there should, in theory, be multiple > possible implementations (and by that, I mean power saving approaches) > that can all interoperate. Indeed. Carles, we're not saying that L3 should not take into account the specific characteristics of L2. This is why we have the following WG item: "- Specification of routing metrics used in path calculation. This includes static and dynamic link/node attributes required for routing in LLNs." There are a few cases where cross-layer "collaboration" may be quite powerful but we need to be very careful at what we're doing here. Thanks. JP. > > Phil > > _______________________________________________ > 6lowpan mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/6lowpan _______________________________________________ 6lowpan mailing list [email protected] https://www.ietf.org/mailman/listinfo/6lowpan
