Further reading
Please refer to the following links for more information:
- For a list of hardware types identified in the ARP header, go to the following: https://www.iana.org/assignments/arp-parameters/arp-parameters.xhtml#arp-parameters-2.
- The Opcode defines what operation the sender is executing. View the entire approved list of Opcodes at the following: https://www.iana.org/assignments/arp-parameters/arp-parameters.xhtml#arp-parameters-1.
- Discover when hosts issue a gratuitous ARP by visiting the following: https://wiki.wireshark.org/Gratuitous_ARP.