On Thu, Feb 19, 2015 at 2:42 PM, Juliusz Chroboczek <[email protected]> wrote: >>> Well, ethernet runs at different speeds and there is no abstraction >>> for that in babel... > >> Why not? > > Switches. > > Most home routers have their (on-chip) Ethernet interface behind an > internal switch. That is how they provide 5 or more Ethernet ports using > a single-NIC SoC.
It is even worse than that. Many of the more modern devices only have a single ethernet device, and they use a vlan trick in order to get an ISP uplink port out of it. This is one of the cases where applying a hardware rate limited aqm/fq system doesn´t work at all, you end up with Hol as everything in all directions vanishes into the switch, and of course things like link detection go by the wayside. Another painful aspect of this is when a box is supplying a default gateway but actually has not achieved internet access. Tools like babel-pinger help, but are not tightly integrated with dhcp. Welcome to the race to the bottom. > That has the unfortunate consequence that neither carrier sense nor link > speed sensing is going to work on most home routers without model-specific > code. > > That is what I allude to in Section 4.3 of the draft, but I see that > I need to be more explicit in -02. Your (plural) feedback is being > helpful. > >> I mean the babel protocol, not current code. > > Oh, if I don't have to implement it, then I'm all in favour ;-) > >> So what I want to see is a proposal for a routing protocol that specify >> link metrics for a set of commonly used link types in homes. > > That's something the IS-IS community has already done, I believe, although > their values might not map directly to Babel metrics (which are just 16 bits > long). > > -- Juliusz > > _______________________________________________ > homenet mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/homenet -- Dave Täht thttp://www.bufferbloat.net/projects/bloat/wiki/Upcoming_Talks _______________________________________________ homenet mailing list [email protected] https://www.ietf.org/mailman/listinfo/homenet
