Yes, Rémi, you are. We have explained that inserting data requires a new header and thus IP in IP encapsulation. This happens for instance when a packet comes from the Internet into a RPL network. Which we can hardly accept in constrained networks an devices. In most cases, we could squeeze the information we need in the Flow Label should it be mutable. Pascal
> -----Original Message----- > From: [email protected] [mailto:[email protected]] On Behalf Of > Rémi Després > Sent: Thursday, August 12, 2010 2:55 PM > To: Pascal Thubert (pthubert) > Cc: [email protected]; Carsten Bormann; [email protected]; Brian E Carpenter; > [email protected] > Subject: Re: [Roll] Flow Label: 12 bits mutable and 8 bits immutable > > > Le 12 août 2010 à 10:47, Pascal Thubert (pthubert) a écrit : > > We'll note that the Hop by Hop + IP in IP is costly but solves the > > generic problem *within* the RPL network. The use of the Flow label > > *within* the RPL network would be an alternate so it could have a more > > limited applicability, like a more limited number of instances or a > > Rank floor that can be expressed in 1 octet or less, which is probably > > more than enough considering that infinity is 16 in RIP. This could > > cover a large number of foreseeable deployments. > > > > There is certainly a strong benefit in Low Power Lossy Networks to > > make the flow label mutable. > > How strong the benefit isn't clear to me. > Since RPL networks are recognized as such by hosts, it seems easy to add a > short field, just before the IP header, to contain whatever is useful for > this kind > of network. > Mixing functions with those of FLs would thus be avoided. > > Did I miss something? > RD > > > > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > [email protected] > Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 > -------------------------------------------------------------------- -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
