(2)Class B: with ACK/NAK protocol. A. Sending
Text to be sent:
T.R.I. Inquiry text
Repeat Run T.R.I. Inquiry text
Start of Test Result Transmission text
Test Result text
Repeat Run Result text
End of Test Result Transmission text
ACK ACK
Received Received
Block end (BCC)
Initial | Start |
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Condition | of | Transmission text |
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| Text |
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| Text end (BCC) |
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| NAK | NAK |
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| 1st time: resending the same block | Received | Received |
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| or | or | |
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| 2nd time: sending the next block | ||
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| 1st time: resending the same text |
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| 2nd time: return to initial condition |
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