1) MAC addresses don't go any further than the local network. Web servers can't see the MAC address of visitors.
If you're going through the same router, every device will show as the same IPv4 address, because of NAT in your router (and possibly CG-NAT in your ISP's network, meaning other connections also use the same IP). However, there are sufficient IPv6 addresses that NAT is unnecessary, so the devices will be separate for IPv6-enabled servers when you're on an IPv6-enabled connection.
2) There's no MAC address on a cellphone radio. The closest thing they have is a IMEI. Again, web servers can't get it. Without physical access to the phone, or access to the mobile network backend, I don't think you can get the IMEI easily. Not sure if phones transmit it in clear.
3) I am not a lawyer. However, any WiFi device transmits it's MAC at the start of every packet in clear, even when the connection is encrypted.
4) If over WiFi, pretty easy.
However, remember that you will have a different MAC for each network adapter. In most laptops, there's one for ethernet and a different MAC for WiFi.
Ok, thanks for this.
Situation is, someone on an internet website is saying they have 'evidence' that myself ( as a user sending messages on this site via iPhone ) and another user were showing as having the same MAC address and IP address.
So... There end looks like me, on my phone with multiple accounts.
However, I know that's not the case.
So firstly I'm concerned they can get this info from my phone. Secondly why does someone have the same?
Could it be someone using my wifi, would our mac addresses show same then if being routed and connected to said website through that??
They say that they have snagged or sniffed my mac and IP address.
Looks to them like 2 people messaging them over the internet with same mac and IP address ( or to them looks like it's me, on my iPhone using multiple
BUT - that's not the case. So it could be that it's someone using another phone through my wifi?
If however myself and this other person whoever it is were using 3G to access the site would they then show as different mac and ip addresses?
If someone had seen my MAC address on my iPhone could they have changed theirs to be the same as mine??
They cannot get the MAC. If they say they can, they're either inside your local network, getting the MAC of their upstream network router (so everybody visiting the site shows up the same), or are lying.
If you're on a CG-NAT connection, you share your IP address with many others.
I've heard it is possible to snag or sniff someone's MAC address if you know what you are doing. This same person even told me what device I was using to access the site!!
I'm just worried because I've never used the site other than for my own account.
So 1, I'm worried said person has this info and 2, it looks bad on me showing 2 accounts from just my phone.
So I need to know is there any way to prove that just because they are showing the same doesn't mean it's categorically me.
You can get the type of device from the User Agent field. That's not a unique identifier though, just device, browser, and software version.
You can get the WiFi MAC, if you're in WiFi range of the device, or are connected to the same LAN as the device. Not through some random server.
As I said earlier, most likely you're on a CG-NAT connection or a fast-shifting dynamic IP. We have some people with 10+ different accounts linked to them, despite the fact that they're completely legit.
What this person is saying is that I've been using my phone for multiple accounts.
What I'm saying is, I haven't, I've only used my phone for my account.
So if she says both have same mac and ip it doesn't PROVE that it's just me , it could
Potentially be a number of different things?
So she could see the MAC address of my wifi but this would be the same for whoever was connected to my wifi, but she can't see my phones MAC address?
So as much as it could look to her like it's me with 2 accounts ( even though we are saying she can't possibly see the MAC address so why would she think this anyway) the info she has doesn't PROVE Anything?
No. She cannot see any MAC addresses of yours, unless she is in range of your access point. As in parked on the side of the road near you. If she was, she'd see the individual MACs, but there wouldn't be any way to associate them with traffic to the site.
No way to prove it, but it certainly raises some flags, particularly if one of the accounts caused trouble.
If somebody else using your internet connection posted on here, the special moderator-only page would have a note that the user was suspected (it's not foolproof) to be the same person. Because most sites, especially those with accounts, take a note of your IP and check if other accounts are the same.