Physical Layer – (AKA The Hardware Layer)

• This Layer Defines how the Cable is attached to the NIC
• Determines how many pins are used
• Determines function of each pin
• The transmission technique
• The duration of the each impulse
• Responsible for transmitting Bits (zeros and ones) from one computer to another
• Packet sent as an unstructured raw bitstream over physical medium
• Hardware-oriented, establishes and maintains physical link between communication computers

Layer 1