The hardware inlucded in this post are Hub, Switch, Router, Modem, AP

1. Physical Layer of OSI#

Hub and Switch#

The purpose of both is to connect the internal network (LAN), they do not know IP

Hub#

It is not intelligent, what it knows is only the ports and the devices that is connected to the ports
It does not filter any data or has intelligence as to where the data is supposed to be sent
When a data packet comes into one port, it will rebroadcast the data to every port that has a device connected to it
It operates at the Physical Layer of OSI

ONU#

ONU (Optical Network Unit) is a device that serves as the demarcation point between the PON and the customer’s premises. It converts optical signals transmitted via fiber optic cables into electrical signals that can be used by devices within the customer’s home or business. The ONU is typically installed on the exterior of a building or inside a utility closet.

PON (Passive Optical Network) is a telecommunications technology used to provide fiber to the end consumer, both domestic and commercial. A PON consists of an optical line terminal (OLT) at the service provider’s central office and a number of optical network units (ONUs) near end users. AON (Active Optical Network) is a point-to-point network architecture that uses electrically powered switching equipment to manage signal distribution and direct signals to specific customers. In an AON, each customer has a dedicated fiber connection to the central office. OLT (Optical Line Terminal) is a device that serves as the endpoint of a passive optical network (PON) at the service provider’s central office. It is responsible for managing and controlling the flow of data between the service provider’s network and the optical network units (ONUs) located at the customer’s premises.

2. Data Link Layer of OSI#

Switch#

It’s intelligent and able to learn physical(MAC) address of devices that are connected to it
When a data packet is sent to a switch, it’s only directed to the intended destination port
It operates at the Data Link Layer of OSI (not including the multilayer switch)

3. Network Layer of OSI#

Router#

It routes or forwards data from network to another base on IP address
It’s the Gateway of a network, it detemines if the packet was meant for it’s own network
It normally works at the Network layer of OSI

Modem#

Modems (modulators-demodulators) are used to transmit digital signals over analog telephone lines

Modulators: it modulates outgoing digital signals into an analog signal
Demodulator: it demodulate incoming analog signals into a digital signal
Modems work on both the Physical and Data Link layers.

Access Point#

A Wireless AP relays data a wired network and wireless devices
It’s basically wireless hub or bridge that’s used by wireless device to connect to an existing wired network
A Wireless AP connects directly to an organization’s router where the router is connected directly to a modem, which gives the wireless device access to the internet
An AP works at the second OSI layer, the Data Link layer

Network Hardware