Dave, My points below are tainted by the fact that I deeply dislike classification -- I'm hoping for solutions in which there's no higher layer knowledge in the routers.
> 1) System control and 'MICE' are < less than 1% of all packets. Mice > includes a bunch of messages like ARP, NTP, UDP, and most of the icmp6 > portion of the stack, in what I'm doing currently. Once you've fought the bloat, there's hopefully no further need to classify these packets. On a working network, you should be able to achieve less than 5% packet loss, even without ECN, and all protocols should be able to support that level of loss. > A) wireless devices are currently making heroic efforts (deep > buffering, exorbitant retries) to get packets through. Seeing a big > delay between transmit time and reception is more an indicator of > congestion than actual packet loss is right now. By the time you see > actual packet loss, the network has often already collapsed > completely. Not for multicast -- there's no link-layer ARQ for multicast in 802.11. That's why RFC 6126 says that you MUST send hello TLVs over multicast only. > C) QoS, Packet marking and prioritization of any sort makes babel > control packets jump closer to the head of the internal queues of the > transmitting clients, thus speeding up routing change propagation. Yes. However, Babel is designed to support loss rates up to 80% or so, and therefore should normally only collapse when your network has already collapsed. (The reason for that? Julien used to have a couch in his office, where the pre-ARQ loss rate to the closest Babel router was well above 50%. We put a lot of effort into ensuring that Julien could read mail on his couch.) > I've also written elsewhere about the effect of multicast traffic on > wireless and am trying hard to stop bridging gigE (1000Mbit) and > Wireless (a,b,g,n) together wherever possible, Hear, hear. (Somebody please bring that up with the OpenWRT folks.) -- Juliusz _______________________________________________ Babel-users mailing list [email protected] http://lists.alioth.debian.org/cgi-bin/mailman/listinfo/babel-users
