ONT state.
data structure:
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| m | ONT state combination | ONT state combination | | ONT state combination |
| (2B) | in Port x | in Port y | ..... | in Port n |
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/ \
/ \
/ \
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| x | ONT m-1 | | ONT 0 |
|(2B) |state(1b)|...... |state(1b)|
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state enum:
normal(0): ONT state is normal.
fault(1): ONT state is fault.