Every single device that’s connected to the internet has one thing in common they all need something called an IP address. Without this address they wouldn’t be able to communicate, browse the web, send emails or anything remotely interesting! It stands for Internet protocol address and is a requirement for using the language of the internet – TCP/IP (Transmission Control Protocol/Internet Protocol).
The addresses actually all look remarkably similar just like this one here – 192.168.1.1, yet they are actually unique. At this point though there is a clarification required between two different sorts of IP address – internal/private and external/public.
As explained every IP address has to be unique, but only on each network. So you could have a private network at home or in the office and you could use any IP address you like as long as you don’t use duplicates on there. However none of these addresses could connect to the internet, unless they had a unique address on there too. Which is why we have this concept of private and public addresses.
Private/Internal IP Addresses
Any address on an internal network. They will not be accessible from the internet and only work on your local devices. You can pick any IP address ranges that you like, as long as they’re in the same ranges as each other. You can change and modify them when you like.
Although you can realistically use any IP address you like, there are some specified ranges that are actually reserved for private networks. You won’t find these used in public facing devices –
- 10.0.0.0 to 10.255.255.255
- 172.16.0.0 to 172.31.255.255
- 192.168.0.0 to 192.168.255.255
They’re normally assigned to network devices which you can buy. So for example if you get a modem or router supplied by your ISP it will often have an address in this range – e.g. 192.168.1.1 or 192.168.1.254.
Public/External IP Addresses
These IP addresses need to be unique on the internet, there can be no duplicates or data will be lost. It would be the same as having two completely identical postal addresses in two completely different places. For home users these addresses are assigned individually to their internet connection by the Internet Service Providers.
This is address that is unique to your connection online, no-one else will have this address which is why it’s something of a concern to privacy activists. If you here someone talking about IP addresses online in most instances it’s this public address they are referring to. Some people also call it an internet IP address too.
So Does my IP Address Change When I Travel then ?
It’s an interesting question, which is actually more relevant than people think. To avoid any confusion it’s probably best to illustrate a brief time line of an IP address through an example day.
- I turn on my digital radio which connect to the internet and brings me the news (home IP address from WIFI router)
- Use my smart watch to check out the weather (home IP address from Wifi router)
- Check my laptop to read email (home IP address from wifi router)
- Get in car and Sat Nav downloads latest updates from internet (Car gets IP address from 4G mobile Gateway)
- Travel by Train to city using mobile phone to browse web (IP addresses from 4G mobile Gateways)
(mobile IP addresses are assigned like this)
- Use Laptop to connect to train’s Wifi Access Point (IP address is assigned from access point)
- Work Office – Plug laptop into company network using ethernet cable on desk (Private IP address assigned locally)
(Laptop actually has private IP address on corporate network but uses public IP address through firm’s web gateway)
- Check email on way home through coffee shop Wifi (IP address from Coffee shops Internet connected router)
- Get Home and switch on Smart TV (home IP address from Wifi router)
As you can see my IP address changes depending on where I am, what device I’m using and how I’ve connected to the internet. Even in this simple timeline I would have switched through about ten different addresses (possibly more depending on how long I used my phone for). I would have also used several distinct types of IP address too –
- Private IP address ranges at home, work and possibly at coffee shop)
- Mobile IP addresses from my Car GPS and mobile phone.
- Public addresses from my home Wifi, Coffee shop access point and company web gateway.
So as you can see although every internet address is unique my own connection will use different addresses throughout the day. My webmail provider will see my account being accesses from a series of different IP addresses during the day depending on where I happen to be at the time.
This is one reason why it’s so difficult for websites to block access to individuals based on the IP address they’re accessing from. If you’ve ever heard of this practice is actually extremely unreliable. For example if I posted an offensive comment on a forum while I was at the coffee shop and the administrator blocked my IP address. They would be in effect blacklisting anyone in the coffee shop accessing that forum. Obviously a registered account is linked to a specific user but they can usually be recreated easily.
How to Change IP Address
From a privacy and anonymity context the main issue is the IP address you use at home. It can be logged, monitored and tracked very easily when you’re online. What’s more it’s registered to a specific location and individual (whoever pays the internet account). A complete record of what this IP address does online exists on the logs at the ISP, plus partial logs at each and every web server that is visited.
Obviously this is likely to be the address you use the most unless you travel a lot, it’s also the most vulnerable. Obviously a home computer is not quite as mobile and will generally always use the IP address assigned to your home account too. So any one who is concerned about they’re online activities being logged or monitored should take steps here rather than when they’re travelling,
You often cannot actually change this address at all, although this is largely dependant on your ISP. Sometimes rebooting you modem/router will get a new public IP address assigned. For most of us though this doesn’t work, you can check by typing ‘what is my IP address‘ into Google which will show your public IP.
If you want a reliable way to hide/change your IP address at home then you should use a proxy or VPN service like this. You can use this to route your traffic through an independent server which hide your real location. If you use a VPN then it will also encrypt your connection meaning that all logs in your ISP are hidden to,
So to summarise, yes your IP address changes all the time depending on where and what you access the internet from. Largely speaking your home IP address which is unique and linked to your physical address doesn’t change. So if you want to mouth off on a forum or social media, then do it with a made up account from a coffee shop or public wifi point!