notes

Short Notes: Data Link Layer

Inner workings to the Data Link Layer, the 'L2' protocol suite.

Krishanu Konar

9 minute read

IP datagrams contain IP addresses, but the physical interface hardware on the host or router to which you want to send the datagram only understands the addressing scheme of that particular network. Thus, we need to translate the IP address to a link-level address that makes sense on this network (a 48-bit Ethernet address). We can then encapsulate the IP datagram inside a frame that contains that link-level address and send it either to the ultimate destination or to a router that promises to…