Can a website identify a specific laptop?

debitcardmayhem

[Deleted User] said:

LV_426 said:

They can probably detect your network card's MAC address. 
I know of at least one forum where the duplicate registration process involved checking this.

Your MAC address is never transmitted outside of your subnet so it is impossible for a website to see the MAC address of your network card.

Your router strips it out when transmitting the data. Your ISP can see the MAC address of your router but not of any of your devices, but once the data leaves their subnet it is replaced with the MAC address of their router and so on until it arrives at the website.

I would be interested in knowing about this forum that can detect the MAC of your NIC? If they insist you download some software which detects it then that is the only possibility I can think of.

I concur with that, MAC addresses are used for level 2 (IIRC) of the protocol and do not ever leave the local network, unless a script is allowed in

prowla

Are they saying you can't use two computers to access your account?

flaneurs_lobster

prowla said:

Are they saying you can't use two computers to access your account?

Much the same as my bank only allowing a single device access to my accounts when using its app.

CKhalvashi

flaneurs_lobster said:

prowla said:

Are they saying you can't use two computers to access your account?

Much the same as my bank only allowing a single device access to my accounts when using its app.

Do you mind me asking which bank this is?

The 2 banks I deal with (both on the high street) will allow me to have access on 2 phones to bank details, as will 2 CC issuers (1 bank, 1 non-bank).

grumbler

prowla said:

Are they saying you can't use two computers to access your account?

Have two accounts with the same computer.

If you use two or more computers for one account bookies for certain customers don't like if  another account is used on the same computers.

flaneurs_lobster

CKhalvashi said:

flaneurs_lobster said:

prowla said:

Are they saying you can't use two computers to access your account?

Much the same as my bank only allowing a single device access to my accounts when using its app.

Do you mind me asking which bank this is?

The 2 banks I deal with (both on the high street) will allow me to have access on 2 phones to bank details, as will 2 CC issuers (1 bank, 1 non-bank).

I've just checked, I'm wrong. Either I've misremembered or my bank have changed their policy.

grumbler

Chase bank is app-only and IIRC it's only one app on one phone.

400ixl

An app installed on a local device is a completely different scenario to the one the OP is talking about, so best not go down that rabbit hole.

It is exceptionally easy to only allow a known user to login to an app on one known device at a time. That is not what we are talking about here.

Belenus

prowla said:

Are they saying you can't use two computers to access your account?

They are not saying anything. They do not respond to messages.

No matter. If they don't want her she will find some other forum.

Thanks everyone for your informative and helpful comments.

FarmerHorse

The answer is yes, forums can do this. I'm not sure how and it's not worth my time speculating on the detail but I've been banned from a couple of forums for being overly enthusiastic about things, and subsequent attempts to sign up with a new ID and different email address from the same PC have been rejected outright.

One of them - Digital Spy fwiw - drops a cookie when rejecting the attempt that then blocks the user from even viewing the discussion boards. Clearing that cookie unblocks read-only to the boards.

On another forum the sign-up is just ignored; I presume there's an identifier somewhere that's passed through and is validated to block a follow-up sign-up.