Handshake Modbus/TCP

asked 2020-06-25 11:30:29 +0000

salwa1215
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I want to know how is the handshake of Modbus/TCP plz. I have a pcap file in which after each reponse of Modbus/TCP) I have a retransmission. That's mean that the server waits for an ACK also ? I thought that Modbus is only request/response communication and the communication stop when the reponse is received ?

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answered 2020-06-25 11:34:23 +0000

grahamb

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Modbus itself is request\response, but when running over TCP, the underlying TCP stacks must obey TCP rules, i.e. retransmit a segment if an ACK isn't received.

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Asked: 2020-06-25 11:30:29 +0000

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Last updated: Jun 25 '20

Handshake Modbus/TCP edit

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