> Op 19 feb. 2015, om 23:42 heeft Juliusz Chroboczek > <[email protected]> het volgende geschreven: > >>> 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. > > 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 ;-)
Bad luck, I kindly ask you to pay a little more attention to it. Link metrics for wireless links are crucial, but let's not forget wired links. Some years ago, Thales NLD worked on olsr-lc (link costs, ETT). A plugin probed WiFi link speed with large & small packets, filtered out jitter and used the outcome as link metric (merged with ETX, I think). For static networks and very patient people, it may work. For mobile networks, it is far, far to slow. Convergence is tens of minutes. Speed up some timers increases load on the wireless links to unacceptable levels. So it died. But for wired links at homes, this plug&play mechanism could work out well. No L2 API needed. http://sourceforge.net/projects/olsr-lc/ Teco > >> 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
