Hacker News Reader

Comment by revjx | Hacker News Reader

I've been avoiding doing this, and I'm not certain the reason is valid - I don't want Google to have my mobile phone number. Perhaps I'm being overly cautious, but the fact Google already collects such a huge amount of data on me, coupled with the increasing insistent requests to enable two-factor with my mobile phone number, has made me not do it. I got so sick of being pestered about it that I stopped using Gmail a little while ago.

View on HN

I can guarantee you that google knows your mobile number already. Do you have friends? do they know your number? do they have you saved as a google contact? game over.

If you are sufficiently paranoid there are probably call/sms-forwarding services available for a reasonable cost.

You don't need to enter your phone number to use Google's two factor. You can use their smartphone application to generate codes. If you don't want to do that, the algorithm is free and open-source so you can probably find an alternate implementation that works fine.

As far as I'm aware, it's not available on Windows Phone 7.

Not GA itself, but there are compatible implementations: http://www.windowsphone.com/en-US/apps/021dd79f-0598-e011-98...

Unless I am mistaken, they won't let you do two-factor auth at all unless you put a phone number first.

I don't think they need a phone number if you use the Google Authenticator app on your phone. The pin for that is generated based on an initial random seed and the current date/time, not your cell number.

They do require it. If you remove it 2-factor-authentication is disabled.

Nothing says that number needs to be your mobile (or one that you have regular access to) but you do need to provide one.

Does that mean that you could use a Google Voice number? Presumably they already know that one, so "divulging" it shouldn't be an issue. ;^)

It's more than a little likely that they already have your number. They have your email address, and chances are that more than a few of your friends have a contact in their google contacts that has that same address alongside your phone number. You could argue that they can't be certain, but aggregated across however many of your friends have those same details stored for you they can make some pretty safe assumptions.

This is the same reason I avoid it. They were insistent about getting my phone number when it was just to verify after a lockout. They've been extremely insistent about it lately regarding 2-factor authentication, which leads me to believe there's a motive here beyond just getting everyone more secure. Until someone can alleviate me of that concern I think I'll have to pass.

Reply on news.ycombinator.com