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How ARP Works: Understanding ARP Requests, Replies, and ARP Cache

 How ARP Works: Understanding ARP Requests, Replies, and ARP Cache Address Resolution Protocol (ARP) is an essential protocol in the world of networking. It's responsible for mapping IP addresses to MAC addresses within a local area network (LAN). 🔄 How ARP Works When a host wants to communicate with another device, it needs the MAC address associated with the destination IP. If the MAC address is unknown, the host sends out a broadcast ARP Request asking: 🗨️ “Who has IP address X.X.X.X? Tell me your MAC address.” The device with the matching IP sends an ARP Reply with its MAC address, allowing communication to begin. 📨 ARP Messages ARP uses two packet types: ARP Request Destination MAC: FF-FF-FF-FF-FF-FF (broadcast) Target MAC: 00-00-00-00-00-00 (unknown) ARP Reply Uses unicast MAC addresses for both source and destination Header Fields Include: Source MAC and IP Target MAC and IP 🧪 Real-World Examples Host-to-Host on Same Network PC2 want...