IMDB Shares Data w/ Amazon.com?

[xiix]

I noticed today on my amazon.com frontpage that the dvd corresponding to a movie I looked up recently on imdb was front and center of the advertised products. I’m pretty sure I never looked that film up on amazon itself, but seeing as how they do own imdb, it doesn’t seem like that big a stretch for the two sites to share data. But would traditional cookies allow for that functionality? I thought it was a 1-to-1 (only sites that made the cookie can access it) dealie. So if its not cookies at work, how did amazon figure out what I looked up on imdb?

shudder

[Brainiac4]

Amazon owns IMDB. The footer on IMDB pages reads:

Copyright © 1990-2007 Internet Movie Database Inc.
Terms and Privacy Policy under which this service is provided to you.
**An Amazon.com company. ** Advertise on IMDb. License our content.

Bolding added.

[ultrafilter]

@xiix

I thought it was a 1-to-1 (only sites that made the cookie can access it) dealie.

I don’t believe this is correct. Anyone who knows the ID of a cookie can request its value.

[gazpacho]

Ultra filter I think you are wrong.

http://www.cookiecentral.com/faq/#3

Scroll done to Domain

Cookies can be assigned to individual machines, or to an entire Internet domain. The only restrictions on this value is that it must contain at least two dots (.myserver.com, not myserver.com) for the normal top-level domains, or three dots for the “extended” domains (.myserver.ny.us, not myserver.ny.us)

IMPORTANT: The server issuing the cookie must be a member of the domain that it tries to set in the cookie. That is, a server called www.myserver.com cannot set a cookie for the domain www.yourserver.com. The security implications should be obvious.

If Domain is not set explicitly, then it defaults to the full domain of the document creating the cookie.

and

4.3 Retrieving a Cookie Value

For the most part, retrieving cookies does not require reading the HTTP Cookie: header. Most languages read this header for you and make it accessible through a variable or object.

Cookies can be read on the browser side or the server side. Again, the determining factor is the language used.

The main limit on retrieving a cookie is that you can only retrieve cookies that are valid for the document your script resides in. That is, a script on www.myserver.com cannot read cookies from www.yourserver.com. This is also true for subdirectories within your site. A cookie valid for /dirOne cannot be read by a script in /dirTwo. This is mainly governed on the browser side, as browsers know the URL that they are accessing, and only transmit cookies for that server across the connection.

[susan]

A while ago I went to IMDB, where I had never registered, and it greeted me by name and knew things about me. I traced the info back to Amazon.

[xiix]

so assuming gazpacho and I are correct, what sort of technology would be in play here? Is it as simple as a shared database? Even that would not explain how amazon/imdb could track my ip.

[Cerowyn]

IMDB and Amazon share information on the server side. A simple system would look like:

1. IMDB serves up a page that contains an embedded session ID.

2. The page requests a frame or image from Amazon, encoding the session ID in the URL.

3. Amazon’s server queries the user’s browser for its 1-Click (or whatever it’s called) cookied ID.

4. Amazon’s server then notes in a table somewhere the relationship between the IMDB generated session ID and the Amazon customer ID.

5. IMDB’s server asks Amazon’s system for the related info.

I don’t know if that’s what’s happening, but it’s pretty straightforward to do.

[xiix]

Brilliant, so IMDB is forcing me to download stuff from amazon.com

why didn’t I think of that!?

[Reply]

Amazon also does (or at least did) the same thing with their affiliates. I was creeped out once when some site I’d never visited before solicited donations from me by my full name. Dunno what Amazon was thinking…

Edit: To be clear, I’m not saying that Amazon shares your search/purchase history with affiliates. In this case, there was a donation button on the site that allowed you to donate using the Amazon Payments system (think that’s what it’s called). It said something like “Hi, Reply. Click here to donate to this site through Amazon!”

[Cerowyn]

@xiix

Brilliant, so IMDB is forcing me to download stuff from amazon.com

why didn’t I think of that!?

Aaaaaand… why else do you think Amazon bought IMDB?

[xiix]

I was well aware of amazon’s evil intentions in buying imdb, my OP was largely concerned with the technique they use to accomlish the datasharing. And more simply, the fact that they now make no secret of their massive CRM-machine.