#2743 HIGH Product: In manufacturing, multicast download of images is highly desirable.

[Zarro Boogs per Child]

#2743: In manufacturing, multicast download of images is highly desirable.
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  Reporter:  jg                   |       Owner:  dwmw2           
      Type:  defect               |      Status:  new             
  Priority:  high                 |   Milestone:  Production Start
 Component:  ofw - open firmware  |     Version:                  
Resolution:                       |    Keywords:                  
  Verified:  0                    |  
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Comment (by dwmw2):

 The 36Mb/s transmission loses a lot of packets. We're told that's more
 than the libertas wireless device can cope with anyway, so this result
 isn't particularly surprising. Perhaps using 36Mb/s packets but actually
 transmitting fewer packets so we're still only transmitting at 24Mb/s on
 average might work, but seems unnecessary.

 All the OFDM rates (12/18/24 Mb/s) seem to have a slightly higher loss
 rate than CCK, but not significantly so -- it seems that the best
 transmission rate is going to be 24Mb/s, with enough redundancy to cope
 with the loss.

 However, in each of the above dumps we see the effect of the occasional
 burst of noise which has taken out a complete eraseblock. This is partly
 because our current scheme transmits a single eraseblock at a time, and
 the effect of a multi-packet loss is not spread between different blocks.
 If we were to transmit packets from different eraseblocks in a round-robin
 fashion, then the effects of such noise would be spread out and less
 redundancy should be required.

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Ticket URL: <https://dev.laptop.org/ticket/2743#comment:6>
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