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Phase 2: Data Transmission■ Normal phase 2The sending station first sends a transmission block containing the heading text.
Each time the sending station receives an ACK from the receiving station, it sends a
transmission block containing the data texts as shown below. Upon receipt of an
ACK in response to the last transmission block (data text n), the sending station
shifts to phase 3.
If a transmission message contains no data text, the sending station transmits the
heading text only.
ACK
ACK
ACK
ACK
Sending station Receiving station
To phase 3.
Heading text
Data text 1
Data text n-1
Data text n