The data link layer is traditionally broken into two sub-layers: mac sub-layer: (media access control) the layer that organizes networked devices by a unique mac address. every networked device has a unique mac address assigned by the manufacturer. llc: (logical link control) the layer that provides error and flow control to other layers, and that is used to provide both connection and connectionless - oriented services. when you think llc, think transport layer - llc is intimately connected to the transport layer as the two work together to provide these two types of services.
