Networking Addresses Overview

Overview

This lecture explains the differences between MAC addresses and IP addresses, their roles in networking, and how they work together to send data.

A MAC address is a device's unique identifier on a local area network (LAN).
Also called the physical address, a MAC address is only relevant within the local network.
MAC addresses are 12 hexadecimal digits, grouped in pairs and separated by hyphens or colons.
They are hardcoded into devices during manufacturing but can sometimes be altered.
Devices communicate locally (e.g., from a laptop to a printer) using each device's MAC address.

An IP address identifies a device on a global network, such as the internet.
Also called the logical address, it is used for communication beyond the local network.
IPv4 addresses are 32 bits, written as four groups of numbers separated by periods.
IPv6 addresses are 128 bits, written as eight groups of four hexadecimal digits separated by colons.
IP addresses are assigned after manufacturing and can be changed by network administrators or automatically via DHCP.

Devices use their MAC address to communicate within the local network and their IP address for internet communication.
Data sent outside the LAN includes both source and destination IP addresses.
Routers use IP addresses to forward data packets between networks.
When data reaches the destination network, the Address Resolution Protocol (ARP) matches the IP address to the correct MAC address for final delivery.

MAC Address — A unique identifier assigned to a network interface for local network communication.
IP Address — A logical identifier assigned to a device for communication on global or external networks.
DHCP (Dynamic Host Configuration Protocol) — A protocol that automatically assigns IP addresses to devices on a network.
ARP (Address Resolution Protocol) — A protocol that maps IP addresses to MAC addresses within a local network.