................................................................................................................................ 561
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29 Layer 2.............................................................................................................. 575
.....................................................................................................................................580
.............................................................................................. 556
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....................................................................................... 560
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................................................................................................... 561
................................................................................................................ 562
................................................................................................. 563
.............................................................................................. 564
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................................................................................................. 567
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.......................................................................................................575
................................................................................................ 575
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.............................................................................................576
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..................................................................................... 578
............................................................................................... 578
......................................................................................... 578
.................................................................................................579
...................................................................................... 579
.............................................................................................................. 582
................................................................................................................ 585
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........................................................................................................................ 587
................................................................................................... 587
......................................................................................................................... 588
..............................................................................563
..................................................................566
.............................................................................. 575
................................................. 580
.............................................................. 583
19