If a network adapter is receiving a packet, it is comparing the packet’s destination MAC address to the adapter’s own MAC address.
Packets that are sent on the ethernet are always coming from a MAC address and sent to a MAC address. Network cards each have a unique MAC address. MAC addresses are the low level basics that make your ethernet based network work. SuperUser contributor Werner Henze offers some insight into the function of the MAC address: Where indeed? What is the specific function of the MAC address? The Answer So my question is, where exactly does a MAC address come into play during a packet transfer? I don’t think it sits there for no reason. So, MAC addresses are not used for packet transfer. With MAC addresses, there is no hierarchy, and thus packet forwarding would not be possible. I understand that IP addresses are hierarchical, so that routers throughout the internet know which direction to forward a packet.
SuperUser reader Vishnu Vivek is curious about MAC addresses and their function:
