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• speed
• difficulty of debugging
• each board needs a CAN transceiver IC
• Needs termination resistors on both ends

Ethernet

Pros

• debugging is easier
  
  • talk to all boards with a standard PC
  • makes testing easier, simulation easier to implement
• works with pre-made tools
  • wireshark for debugging / capture of the network for playback
  • don't need to implement some kind of discovery protocol, just use ping
  • need some other functionality? it probably already exists
    • TFTP
    • SNTP
    • PTP
• ground hardware become trivial
  • forward network packets identically
• speed
• Ethernet device ICs cheap (Wiznet W5500)

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