Explanation
A router is a device that can dynamically distribute an IP address to the devices connected to its network using a protocol called DHCP (Dynamic Host Configuration Protocol). DHCP allows a router to automatically assign an IP address and other network configuration information to a device when it joins the network, without requiring manual intervention from the administrator. A router can also act as a gateway between different networks, such as a local area network (LAN) and the internet1.
A hub is a device that connects multiple devices on a network and forwards data packets between them.
However, a hub does not assign IP addresses or perform any routing functions. A hub operates at the physical layer of the OSI model and does not understand IP addresses or other network protocols.
A switch is a device that connects multiple devices on a network and forwards data packets between them based on their MAC addresses. A switch can improve the performance and security of a network by reducing collisions and isolating traffic. However, a switch does not assign IP addresses or perform any routing functions. A switch operates at the data link layer of the OSI model and does not understand IP addresses or other network protocols.
An injector is a device that provides power to another device over an Ethernet cable, such as a wireless access point or a security camera. This is also known as Power over Ethernet (PoE). An injector does not assign IP addresses or perform any routing functions. An injector operates at the physical layer of the OSI model and does not understand IP addresses or other network protocols.