Thomas, MingAnn, Sorry for the late response. See inline.
On Wed, Mar 6, 2013 at 8:38 PM, Thomas Pedersen <[email protected]> wrote: > On Wed, Mar 6, 2013 at 4:59 PM, MingAnn Ng <[email protected]> wrote: >> Hi Thomas and Yeoh, >> >> >> I have successfully compile compat-driver-3.8-1 and run it on my system. I'm >> having 3 nodes near to each other and the signal strength between them are >> about 45dBm to 65dBm. From a particular node, I continuously ping the other >> two nodes for more than 14hours. Ping result to one of the nodes has no >> duplication and packet loss. Ping result for the other node are: out of >> 50453 packet received, there are 590 duplicated without any packet loss. > > It is possible that this will happen if the path selection algorithm > determines a multi-hop path is in fact "better". This bit of code in > net/mac80211/rx.c: > > /* Frame has reached destination. Don't forward */ > if (!is_multicast_ether_addr(hdr->addr1) && > ether_addr_equal(sdata->vif.addr, hdr->addr3)) > return RX_CONTINUE; > > will accept frames as long as the DA matches the local address. Then > the receiving node will get both the original and forwarded frame (if > it is in range, of course). Maybe this is an argument for only > matching against TA? Except IEEE 802.11-2012 9.32.4.2(b) actually > states that this is the right address to check. I'm afraid I don't understand your explanation. Can you draw a simple message sequence chart that shows the scenario where a node would receive duplicate unicast frames? Have we been able to replicate? MingAnn, do you have a sniffer capture that we can use to validate Thomas' hypothesis? I would only recommend introducing the recently uncast cache Yeoh is proposing if we understand the root cause why duplicate unicast frames occur. Cheers, Javier -- Javier Cardona cozybit Inc. http://www.cozybit.com _______________________________________________ Devel mailing list [email protected] http://lists.open80211s.org/cgi-bin/mailman/listinfo/devel
