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Notes: The Data Link Layer in Detail
How does a computer know that a message was intended for itself?
The Data Link Layer (DLL) is the second layer in the TCP/IP model. The DLL defines a standard way of interpreting the signals sent by the Physical Layer so that network devices can communicate.
The primary purpose of this layer is to abstract the Physical Layer, so other layers in the stack don’t care what kind of hardware is in use (e.g., cable, wireless, etc.). Thus, the Network, Transport, and Application layers can now operate in the same way, no matter how the device they are running on is connected.
At this layer, we introduce our first protocols. The most common protocols at the Data Link layer are the Ethernet and Wi-Fi protocols.
Beyond specifying Physical layer attributes, the protocols on this layer also define a standard responsible for getting data to nodes on the same network or link.
This story is part of the “notes” series. “Notes” stories are just this; my notes on various things I read about. I…
