MDS 05-4846A01, Rev. D SD Series Technical Manual 15
Packet With MAC is the recommended method of operation when both
serial ports are used to pass payload data if there are two hosts (e.g., Post
Sharing with multiple host case). If there is a single host polling all units,
packet or transparent mode is the better option (depending on whether
encryption is required or not) even if there are two RTUs connected to a
remote radio.
Figure 10. Serial Remotes with Two Serial Ports
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