The physical layer in computer networks is responsible for transferring data between digital and analog signals. It ensures that the data is transmitted in the correct format through the physical network, such as Ethernet or Wi-Fi, and that the receiving device can interpret it correctly. We will now explain how the physical layer works in both Ethernet and Wi-Fi networks.
Ethernet network
In Ethernet network, the physical layer uses electrical transmission to convert digital bits into analog electrical signals and transmit them through network media, such as Ethernet cable. This process is done through modulation, where a sequence of bits is converted into electrical impulses that represent zeros and ones.
When data transmission occurs via an Ethernet cable, the digital signal is conveyed as electrical impulses. The physical layer receives these impulses and converts them back into a digital format that the computer can understand and process. This is how information is physically transferred from one device to another in the network.
Wi-Fi network
In a Wi-Fi network, the physical layer uses radio frequency transmission to convert digital bits into radio frequency signals and transmit them through wireless media, such as airborne radio broadcasts. This process is implemented using modulation techniques, such as Quadrature Amplitude Modulation (QAM).
When data transmission occurs on a wireless Wi-Fi network, the computer sends radio signals to a wireless access point. The access point receives the signals and converts them back into digital form so that the data can be transmitted towards the network. The same process occurs in the opposite direction when data arrives wirelessly from the access point to the computer.
Sum total
This is how the physical layer works in both Ethernet and Wi-Fi networks, ensuring that digital data is transmitted correctly through the physical network. It takes care of converting signals from digital to analog form for transmission and receives analog signals in the opposite direction, converting them back into a digital format that computers can understand and process.
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