Can a blogger ID specific readers by IP address?

March 11, 2008 10:50 PM

Can a blogger tell that I am reading their blog by my IP address?

I read a Blogger/Blogspot blog in my Google Reader feed. Can the owner of the blog tell that I am reading it by my IP address?

A while ago, I subscribed to the blog of an eccentric friend of a friend for the lulz. This blogger just fired off a post saying that she knows who is reading it because of the IP addresses, and called out all unauthorized readers as "stalkers." I'm a little creeped out, since I didn't really want this blogger to know I was reading her posts and want to avoid any drama. Is it actually possible for a blogger to ID specific readers by IP address?

Apologies for my ignorance, but my understanding of how IP addresses work is that (unless you are mathowie caliber) a person can only find out a region and city from an IP address, but not a specific name. Wouldn't someone have to petition a ISP to find out a person's name?

Thanks in advance, and further apologies for a question that I'm sure is quite basic.

posted by Locative to computers & internet (23 comments total)

Also: if I read a blog through my Google Reader, does this identify me by my Google Account to the owner of that blog?
posted by Locative at 10:51 PM on March 11, 2008

You definitely can't identify a person from an IP address, as you say. Generally speaking*, only the ISP can make a connection between an IP address and a person/physical address. Law enforcement people can do it with a court order to the ISP. There's no magic way of doing it like you might see on a TV show. And no, Google reader isn't passing on your IP address, only their own.

* To be less vague, if a person had physical access to your computer and could look up its IP address, then yes, they could make the match the other way around. But not the way you're thinking.
posted by AmbroseChapel at 11:03 PM on March 11, 2008

If you've emailed the person (which carries an IP), then yeah, there's a reasonable chance your IP can be linked to your identity. I run a large forum and that's one way I attempt to investigate trolling problems. However an IP address changes by the minute if they're travelling, or typically by the day or week if they're on a home account, so your mileage may vary.
posted by tinkertown at 11:07 PM on March 11, 2008

Thanks for the responses.

To clarify, I've never e-mailed the blogger, nor have I commented on her blog.
posted by Locative at 11:11 PM on March 11, 2008

The way that I have my blog set up I use google analytics which is most likely what that person is using. However google doesn't allow you to see peoples IP addresses. How ever you can find out country, state, city, network name. So they could just be guessing on knowing what area people are reading from.
posted by lilkeith07 at 11:11 PM on March 11, 2008

Someone can find out a region, a city and an ISP from an IP address. If they think they know these things about you already, and your location details are fairly unique, then they could make some educated guesses and come to some broad conclusions.

If you have had some kind of personal contact with the blog, such as leaving a comment, then they could obviously match this up with your IP again in the future, although IP addresses constantly change, and it would never be a certain identification.

And, if you're reading things through Google Reader, then there's effectively a barrier between you and the blog - Google will only identify itself to the blog as Google, and will not pass on your account details or IP address.

Meanwhile, I'm humored by the idea of someone calling people who read a public website "stalkers"...
posted by Jimbob at 11:15 PM on March 11, 2008

A while back I was able to track a blog-reader IP to a specific government branch by the power of google. I was looking to see if an acquaintance was reading my posts and I knew where he worked. Be careful if you're reading from a publicly-funded computer!
posted by rhinny at 11:17 PM on March 11, 2008

This blogger just fired off a post saying that she knows who is reading it because of the IP addresses, and called out all unauthorized readers as "stalkers."

This fascinates me, the idea that someone would post something accessible to the whole wide world and then get upset that the public might be reading it. Eccentric indeed.

On IP address alone, it's dependent purely on the connections you leave behind. For instance, if you surf through a static IP (as I do) and host a web site on that same IP (as I do) and have your real name and address on the domain name registration (as I do) then hey, you're identified. On the other hand, if you're even slightly more discreet than I am, you have no worries whatsoever.
posted by davejay at 11:28 PM on March 11, 2008

I have friends who sometimes use the contact form on my website to send me 'threatening' messages. I have their IP but the only reason I know it's them is because of the city/school/location behind the IP, and I make a guess. So if you are in some random location, or are studying at some school and the blogger knows this, they could guess that it's you but they won't have anything concrete to base it on.

I really wouldn't worry about it.
posted by 913 at 11:32 PM on March 11, 2008

Depending on how the blog is set up, the blogger can see: your IP address, what OS and browser you use, your screen resolution, and the time that you viewed the site.

If you have a fixed IP address, do a Google search on it. If you've ever posted to Usenet from it, if some other site that logs IP addresses has published it next to your name (some message boards do this to discourage trolls), then yes, the blogger can make a good guess that it's you at that IP.

From a reverse lookup on the IP, the blogger can probably tell what region you are in (possibly down to the city). They can fairly reliably tell what country you are in, certainly.

The combination of these pieces of evidence: time of day, geographical region, OS, browser, and screen resolution may be enough for the blogger to identify you, especially if they already know you and suspect you may be the visitor.

On the other hand, if you're a random visitor, and you don't have a fixed IP address, chances are slim short of a subpoena to your ISP.
posted by zippy at 11:44 PM on March 11, 2008

And, if you're reading things through Google Reader, then there's effectively a barrier between you and the blog - Google will only identify itself to the blog as Google, and will not pass on your account details or IP address.

Images embedded in the blog do not get redirected through google, so the blog owner can still see the IP addresses of readers by looking at the download logs for their images. Their may be other similar methods using other embedded media, ads, or javascript wizardry.
posted by IvyMike at 11:49 PM on March 11, 2008

There have been cases where I wanted to know more about a visitor and only had their IP to work with. I have turned up a surprising amount by googling for the IP itself. For instance, in one case I was able to come up with a name, because a discussion system kept its access logs publicly available and the google spider had found the logs, and the person of interest was a member. The log connected the IP to the member name, and then I was able to look at the member page on that site.

If you really want to protect yourself, visit using a proxy like Anonymouse.
posted by Class Goat at 12:15 AM on March 12, 2008

why doesn't she password-protect her blog?
posted by matteo at 4:47 AM on March 12, 2008

If you read it from work, they may be able to see your company's name very easily.
posted by lampoil at 5:07 AM on March 12, 2008

If you want to see what people can find out casually about you from your IP address, check out http://www.ip-adress.com/.
posted by SteveInMaine at 5:35 AM on March 12, 2008 [6 favorites has favorites]

Wow, Steve--that link figured out not only where I work, but which department. No, it didn't have my actual name, but that's pretty damned granular.
posted by MrMoonPie at 7:00 AM on March 12, 2008

Blogger allows you to add custom javascript sections to their blog. If the blog owner was technically inclined, it would be fairly simple to write a script that stored your ip address. Google Analytics can also be used for something similar, and it tracks IP addresses back to cities, but doesn't give you much more than that.

If they have your ip address, and your computer is connected directly to the internet (without a router or NAT), and your computer has an obvious name "JIM_SMITHS_COMPUTER", I'm sure some enterprising young whipper-snapper could figure it out.
posted by blue_beetle at 8:00 AM on March 12, 2008

There's a fair amount of discussion about IP addresses and how they work on this blog post of mine:

What's the big fuss about IP addresses?
posted by Caviar at 9:39 AM on March 12, 2008

I have tech-savvy friends who occasionally mention things like "I saw [company name] on my logs today... What'd you think of the blog entry?" because they know I work for that small company. SteveInMaine's link figured out my company name with no trouble, too. So if you're surfing from work, that might give someone an extra clue about who you are.
posted by vytae at 9:45 AM on March 12, 2008

If you're only reading her blog via Google Reader, she shouldn't be seeing your IP at all, since it's Google that's pulling her content in. Your machine never directly requests anything from her server. If you're hitting the box directly on occasion, though, then we get into all the questions of whether you have a fixed IP address, or if it's part of a block assigned to a business she knows you work for, etc. Frankly, it sounds like your eccentric friend is full of it, and since she is publishing her blog for all to read, I'm tempted to say that you should share the URL with us. Just, you know, for the lulz.
posted by mumkin at 11:29 AM on March 12, 2008

Your machine never directly requests anything from her server.

That's not necessarily true. There are all kinds of leaks possible. For example, embedded images will likely be fetched directly from the host. I don't use Google Reader, so they may be proxying those too, but my guess would be that they aren't.
posted by Caviar at 12:18 PM on March 12, 2008

embedded images will likely be fetched directly from the host

Oh, curses, you're right. I was looking at a feed that didn't embed images. Shorpy does, however, and yes, the images in that feed are being loaded directly from the server. Right then, so there's your IP potentially revealed, for what it's worth. I still suspect Locative's eccentric friend-of-a-friend of bullshitting, though.
posted by mumkin at 12:30 PM on March 12, 2008

A belated thanks to everyone for their responses.
posted by Locative at 7:09 PM on May 5, 2008