What is the difference between MAC addresses and IP addresses? If all network adapters have MAC addresses, why do we need IP addresses?

MAC (Media Access Control) addresses and IP (Internet Protocol) addresses both serve the purpose of identifying machines on a network, but they operate at different levels of the network and serve different purposes.

1. MAC Address:

   • A MAC address is a unique identifier assigned to network interfaces for communications on the physical network segment.
   • It operates at the data link layer (Layer 2) of the OSI (Open Systems Interconnection) model.
   • MAC addresses are used in the local network and are not routable, which means they cannot be used to send data between different networks.
   • They are permanently burned into hardware by the manufacturer, although they can be changed through software.

2. IP Address:

   • An IP address is a unique identifier for a device on a network that is used for routing data across the internet or a local network.
   • It operates at the network layer (Layer 3) of the OSI model.
   • IP addresses are routable, which means they can be used to send data between different networks.
   • They can be dynamically assigned and can change over time or when moving between networks.

The reason we need both MAC addresses and IP addresses is because they serve different purposes in networking. MAC addresses are necessary for communication within a local network segment, while IP addresses are necessary for finding devices across different networks and routing data to them.

In a typical scenario, when a device wants to send data to another device, it uses the IP address to find the general location of the destination (i.e., its network) and the MAC address to find the specific device within that network.