On Sep 15, 2010, at 8:51 AM, Carsten Bormann wrote: >> Has anybody discussed adding a header with just the 3 bytes you need >> *before* the IP header? > > Yes. Ever since you proposed pretty much that at a previous IETF meeting, > I've been thinking that architecturally it makes a lot of sense to think > about ROLL as a sub-IP protocol.
Architecturally RPL is not a "sub-IP" protocol, but lies at the networking layer. Remember that RPL is link layer "agnostic" and no assumption is made on the link layer. > >> The downside is that you need a new code point (for demux) in the different >> layer2s that you want to run this on. > > And that is exactly the non-starter about the general proposal. > It is not acceptable to require a new spec for each of the many link layers > we want to run ROLL on, in particular for those who don't really care that > much about the overhead. > > However, it would be pretty easy to put something in 6lowpan to carry those 3 > bytes. > (Consider it an advanced form of header compression for the 48-byte IP-in-IP > thing, if you don't like the sub-IP thinking.) > Consult http://tools.ietf.org/html/draft-bormann-6lowpan-ext-hdr-00 for a > sample base design. > Such a simple extension may actually be a preferable way to carry ROLL in > 6lowpan. "preferable" in which sense ? Thanks. JP. > > Gruesse, Carsten > > _______________________________________________ > Roll mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/roll -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
