The Address Resolution Protocol (ARP) was designed to resolve IP addresses to MAC addresses. The importance of ARP is sometimes underestimated among IT professionals. All the communication between devices on a local area network (LAN) or within the same subnet uses the Media Access Control (MAC) address. This means that the devices do not use an IP address unless the communication is going beyond their local subnet, such as to another network (or subnet).
Let's use a simple analogy of a PC that wants to send a document to be printed out to the network printer. If these two devices are on the same subnet, the PC will encapsulate its message (document) within a frame and send it to the network switch. The network switch will read the destination MAC address of the frame and forward it to the network printer for processing.
Let's take a...
