Explain IP addresses, please.

WIAWSNB

Just summat I noticed whilst doing lots of broadband speed tests recently. When it displays the result, it also shows the IP address, with a caption, "Hide IP address.", which I guess is an option.

The thing is, the number shown is different every time I run a test on the same phone and same SIM. So presumably the IP address cannot ID me in any sense whatsoever as it always changes? Ie, it ain't an issue?

Is it 'cos it's a phone running on a network, as opposed to a PC with a fixed router? Does the latter have a fixed IP?

Ta.

vacheron

Most consumers have what is called a dynamic IP address, so it changes from time to time, usually every time you restart your router or phone, or disconnect and reconnect to the internet.

Larger companies and businesses tend to have Static IP Addresses, but these are much more complicated and expensive.

So you are correct that your IP address can (and will) change, but each time that new IP address is "loaned" to you by your internet provider (sky or virgin for broadband, or EE / Vodafone etc, for your mobile) from a bank of addresses that they have.

Therefore, if you did visit a site, and this site logged your address, your internet provider could link your login details to that address, and therefore know who (or at least which account) it was.

On top of that your internet provider may (most likely will) keep logs of all the sites your account visits, and what IP address you were allocated at the time.

Ayr_Rage

If you are testing via mobile data rather than through your home router you'll get a new IP address each time your phone connects to a different cell site.

WIAWSNB

Thanks, both - that's all very clear.

Frozen_up_north

Also of note is that mobile networks use carrier grade network address translation (CGNAT), which can allocate several users to a single IP v4 network address. This effectively stops you being able to accept incoming connections unless you run a VPN as a private network, for exampe, if you want to use the mobile network with your remote CCTV and monitor it from elsewhere.

The free solution to being able to access your mobile router is Tailscale, which is free for up to 3 users and 100 devices. I have been using Tailscale for a long time and it is a reliable and secure means of using a cheap data SIM for remote access.

https://en.wikipedia.org/wiki/Carrier-grade_NAT
https://tailscale.com/

WIAWSNB

Er, thanks, FuN. That's er, whoooosh over me 'ead :-)

WIAWSNB

Er, thanks, FuN. That's er, whoooosh over me 'ead :-)

vacheron

https://forums.moneysavingexpert.com/discussion/comment/81972256#Comment_81972256

I also thought that was quite a tech level jump from the original question when I read it. 😉

I do use Tailscale though to allow me remote access to my Home Assistant Green server without having to pay their monthly subscription. 👍️