- Sends the bit stream - electrical impulse, light or radio signal , through the network at the electrical and mechanical level.
- It provides the hardware means of sending and receiving data on a carrier,
- Carrier includes cables, cards etc. like Fast Ethernet, RS232, and ATM are protocols with physical layer components.
Data Link Layer
- Switching and routing technologies work in this layer
- Logical paths, known as virtual circuits, for transmitting data from node to node
- Addressing and packet sequencing.