Here's the definitive answer: this "new EBAY policy," if implemented, has nothing to do with what PC or MAC (computer you are on). Nothing to do with MAC (Media Access Control) address. It has to do with cookies.
Do your own research.
Go to a banking website like
www.bankofamerica.com , that you use for online banking. Log in using firefox, set to delete cookies on each restart. Due to the lack of cookies, the system will tell you that it does not recognize your computer, and ask you to answer one or more of your secret questions. Prior to that it will ask you what state you are in. All this is not because it does not recognize your computer - the website has no way of knowing what computer you are using, but simply because your cookies are cleared.
The interesting thing is....
Then quit firefox, which will delete the cookies, and log in again. Although cookies are gone, this second time using firefox the website will claim to recognize your computer.
Now, this is not the first time I have logged into my bank accounts using that banking website. I've done it many times on this same computer using my Safari browser, which is not set to delete cookies. And yet, when I tried it with firefox, set to delete cookies, at least on the first try the system claimed not to recognize my computer.
So it seems that cookies have something to do with it. But then...when cookies are deleted and firefox restarted, why would the website recognize my computer the second time? After all, the cookies are still gone.
You see what I mean - if the system could truly determine what computer I am using, it would not matter what browser I am using or what cookies are present. But then, if cookies are the sole answer, then why would the website figure out what computer I am using even with cookies deleted?
One thing is clear - with cookies deleted the banking website asks every time what state I am in. So that much, it is unable to discern without cookies. So cookies are definitely part of the answer here, maybe the whole answer.
This needs more research. More data.
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Here is what typical banking websites say about "recognizing your computer," and it does seem to imply that it is all about cookies:
http://www.vigproduction.cz/en/privacy-statement.php
Cookies
If you visit our website, we may save cookies in your computer, to identify you at the time of your next visit. With cookies, we may e.g. customize the website to meet your requirements or save your password, so that you don’t have to type it every time. If you wish to prevent us from recognizing your computer, please, configure your Internet browser to delete cookies from your hard drive, to block all cookies, or to warn you before saving any cookies. http://www.secuwa.org/home/news.whats_new
# Re-register your computer if, to fix a problem, you must delete "cookies." Enhanced Online Security uses secure cookie technology to identify your computer. If your cookies are deleted, your computer will appear to the system as unregistered. When you try to access your online account, you'll be asked the challenge question. After successfully answering it, you can re-register your computer by going to User Options, "Enhanced Online Security," and selecting "Add extra security to this computer (Recommended)," clicking the Submit button, and selecting "OK" on the confirmation screen. http://www.tcbk.com/personal/multifactor-authentication.aspx
7.) When will I be asked to answer Security Questions?
You may be required to answer a security question at various times based upon your typical online banking activity. For example, you may be asked to answer a security question when accessing the system from a different computer or if you access the system at a time that is inconsistent with your previously established usage. You may also be asked a security question after deleting the cookies in your web browser.
In the end, even if deleting cookies leads to issues with EBAY, just set aside ONE of your browsers for EBAY, and never log into your EBAY account with anything other than that one browser. Use that browser for EBAY only. If you have just one EBAY account, you will have no problems.
If you have multiple EBAY accounts, then you may need more than one browser (Safari, firefox, Netscape, Mozilla, Opera, etc.) One browser for each EBAY, dedicated to that EBAY account only and for nothing else.
There are always alternatives.
