Hi, I had a read of the RATP spec at https://www.rfc-editor.org/rfc/rfc916 The goal is to detect one end trying to start a fresh connection while another is established but manages to be a bit too broad by specifying that any SYN is an error rather than a SYN without an ACK. There seems to be two solutions here: - Don't re-send SYN packets - Break the spec and check if ACK is set before terminating the connection John.
