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Phase 2: Data Transmission
■ Normal phase 2
The sending station first sends a transmission block containing the heading text.
Each time the sending station receives a sequence of DLE ACK and IDs from the
receiving station, it sends a transmission block containing the data texts as shown
below. Upon receipt of a sequence of DLE ACK and IDs 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.
Sending station
Receiving station
Heading text
Data text 1
Data text n-1
Data text n
DLE ACK and IDs
DLE ACK and IDs
DLE ACK and IDs
DLE ACK and IDs
To phase 3.