IP and MAC addresses
People often get confused trying to understand the difference between IP and MAC addresses.
An IP address is the location of your device on the internet, whilst a MAC address identifies the actual device.
What is an IP address?
An IP address (Internet Protocol address) is the unique identification number given to every device that is connected to the internet.
It represents the unique location on which you are connected to the internet, allowing devices all over the world to communicate with each other.
Without these unique location addresses, data could not be transmitted between devices accurately.
IP addresses are similar to your postal address, you cannot expect to get letters to your home unless you have a unique way of identifying it from all the other homes.
When connecting to the internet, you are assigned an IP address to use for your session. This is issued by your network or ISP.
If you take your laptop to McDonalds and connect to the internet, the IP address will differ from when you connected to the internet in Starbucks. This is because the location you are using to connect to the internet has changed.
An Internet Service Provider (ISP) will assign your home with an IP address for your family to use. These are usually dynamic address that may change from time to time, unless you pay extra for a static address that never changes.
An IP address may look like: 220.127.116.11
IPv4 and IPv6
There are two versions of IP; IPv4 and IPv6.
IPv6 was developed to allow the internet to grow by increasing the amount of unique IP addresses available.
This is important because the amount of people and devices needing internet connections now exceeds the limits of IPv4 addressing.
IPv6 uses 128 bit addresses, rather than 32 bits. This is expressed in the form of eight groups of hex digits.
An IPv6 address may look like: A1FB:7A18:FFF0:0FAF:3D81:2085:69FB:F0FB
Public and Private IP addresses
Private IP addresses are assigned by a router for use within a private network.
The IP address is unique within that private network but might be the same as an IP address on a separate network.
Devices directly on the internet, such as your router, are given a public IP address (usually by your ISP).
No other device on the internet should have the same public IP address.
All the devices connected to the router will share the same public IP address (visible to the outside world) but will also have their own unique internal private IP address for use within that private network.
What is a MAC address?
A MAC address (Media Access Control address) is a unique number that identifies the actual device that is connected to the internet or network.
A MAC address does not change when you connect to the internet from different locations, it is part of the network interface card (NIC) inside your device (created at the point of manufacture).
A MAC address is made up of 48 bits, shown as 6 groups of hexadecimal digits.
A MAC address may look like: 00 12 0E A6 B0 68
The first half of a MAC address will identify the manufacturer of the device (or NIC). The second half is the serial number of the device.
MAC addresses play an important part in the transmission of data on a network.