# Link Layer ![[Link Layer - Wikipedia#^gv8nvp]] ^tqa0q9 The protocol data unit of link layer protocols is called a *frame*. We can say that the link layer is responsible for relaying frames between hosts on the same network. ^wic4cs The [[ARP|Address Resolution Protocol]] belongs to the link layer although this classification is subject to interpretation ![[ARP#^7z7e9z]] ## Link Layer Addressing Each link layer host is addressed using a Media Access Control (MAC) address. ![[Introduction to Networking - MAC Addresses#^pyalcx]] ## Comparison to OSI Model's Data Link Layer ![[OSI Layer 2 - The Data Link Layer#^svpzvb]]