Multiple PLCs connected to the switch
Ethernet switch connect multiple PLCs to achieve a distributed control system. One-to-many Network Area Translation (NAT), which may also be referred to as Port Area Translation, is a networking service that allows one static public IP address (the "one") to be accessed by many private IP addresses (the "many"), allowing communication between multiple devices on different. Each panel operates independently and includes its own network devices such as PLCs, HMIs, VFDs, etc. It should be possible to daisy chain the PLCs, as long as they have 2 Ethernet ports. Every recent Siemens PLC I know of has a dual port switch (both ports share the same IP address) except the 1200s (and even then the 1215 has one), specifically so you can either daisy chain them, or form a ring. For example, Company A's driver (serial communication) is set to COM1 and Company B's driver is set to COM2 (serial communication).
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