#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):

 Some early test results from a single XO receiver in a meeting room in
 Quanta's production facility, placed quite close to the transmitting AP.
 Earlier tests with three units spread over a larger distance in the hotel
 room showed not a huge amount of variation -- we'll have to repeat this
 kind of thing in the factory environment and with more receivers to get
 more valid results, but these are a start...

 Streaming an image by multicast, one eraseblock at a time with 93 data
 packets + 15 extra packets for redundancy.

 When sending at 36Mb/s, it's quite lossy; many times round the 'carousel'
 were required:
 {{{
 Number of blocks with 56 packets received: 1
 Number of blocks with 57 packets received: 0
 Number of blocks with 58 packets received: 0
 Number of blocks with 59 packets received: 0
 Number of blocks with 60 packets received: 0
 Number of blocks with 61 packets received: 0
 Number of blocks with 62 packets received: 0
 Number of blocks with 63 packets received: 0
 Number of blocks with 64 packets received: 1
 Number of blocks with 65 packets received: 0
 Number of blocks with 66 packets received: 0
 Number of blocks with 67 packets received: 1
 Number of blocks with 68 packets received: 3
 Number of blocks with 69 packets received: 1
 Number of blocks with 70 packets received: 2
 Number of blocks with 71 packets received: 3
 Number of blocks with 72 packets received: 0
 Number of blocks with 73 packets received: 2
 Number of blocks with 74 packets received: 3
 Number of blocks with 75 packets received: 2
 Number of blocks with 76 packets received: 0
 Number of blocks with 77 packets received: 1
 Number of blocks with 78 packets received: 1
 Number of blocks with 79 packets received: 1
 Number of blocks with 80 packets received: 2
 Number of blocks with 81 packets received: 2
 Number of blocks with 82 packets received: 2
 Number of blocks with 83 packets received: 2
 Number of blocks with 84 packets received: 4
 Number of blocks with 85 packets received: 4
 Number of blocks with 86 packets received: 8
 Number of blocks with 87 packets received: 14
 Number of blocks with 88 packets received: 14
 Number of blocks with 89 packets received: 55
 Number of blocks with 90 packets received: 234
 Number of blocks with 91 packets received: 409
 Number of blocks with 92 packets received: 437
 Number of blocks with 93 packets received: 358
 Number of blocks with 94 packets received: 240
 Number of blocks with 95 packets received: 176
 Number of blocks with 96 packets received: 160
 Number of blocks with 97 packets received: 227
 Number of blocks with 98 packets received: 303
 Number of blocks with 99 packets received: 246
 Number of blocks with 100 packets received: 137
 Number of blocks with 101 packets received: 77
 Number of blocks with 102 packets received: 51
 Number of blocks with 103 packets received: 38
 Number of blocks with 104 packets received: 31
 Number of blocks with 105 packets received: 25
 Number of blocks with 106 packets received: 7
 Number of blocks with 107 packets received: 2
 Number of blocks with 108 packets received: 2
 }}}

 When sending at 24Mb/s it's a lot better:
 {{{
 Number of blocks with 97 packets received: 1
 Number of blocks with 98 packets received: 0
 Number of blocks with 99 packets received: 1
 Number of blocks with 100 packets received: 0
 Number of blocks with 101 packets received: 2
 Number of blocks with 102 packets received: 1
 Number of blocks with 103 packets received: 0
 Number of blocks with 104 packets received: 5
 Number of blocks with 105 packets received: 15
 Number of blocks with 106 packets received: 37
 Number of blocks with 107 packets received: 153
 Number of blocks with 108 packets received: 1865
 }}}

 At 18Mb/s, it looked like this:
 {{{
 Number of blocks with 46 packets received: 1
  ...
 Number of blocks with 87 packets received: 1
  ...
 Number of blocks with 101 packets received: 1
 Number of blocks with 102 packets received: 0
 Number of blocks with 103 packets received: 0
 Number of blocks with 104 packets received: 5
 Number of blocks with 105 packets received: 11
 Number of blocks with 106 packets received: 41
 Number of blocks with 107 packets received: 160
 Number of blocks with 108 packets received: 1862
 }}}

 At 12Mb/s:
 {{{
 Number of blocks with 78 packets received: 1
  ...
 Number of blocks with 82 packets received: 1
  ...
 Number of blocks with 101 packets received: 1
 Number of blocks with 102 packets received: 0
 Number of blocks with 103 packets received: 3
 Number of blocks with 104 packets received: 8
 Number of blocks with 105 packets received: 16
 Number of blocks with 106 packets received: 45
 Number of blocks with 107 packets received: 201
 Number of blocks with 108 packets received: 1806
 }}}


 At 11Mb/s:
 {{{
 Number of blocks with 53 packets received: 1
  ...
 Number of blocks with 103 packets received: 1
 Number of blocks with 104 packets received: 0
 Number of blocks with 105 packets received: 1
 Number of blocks with 106 packets received: 12
 Number of blocks with 107 packets received: 44
 Number of blocks with 108 packets received: 2022
 }}}

-- 
Ticket URL: <https://dev.laptop.org/ticket/2743#comment:5>
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