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Gmail blows up e-mail marketing by caching all images on Google servers

arstechnica.com

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Re: Gmail blows up e-mail marketing by caching all images on Google servers

#32
post #27
post #12

> E-mail marketers will no longer be able to get any information from images—they will see a single request from Google, which will then be used to send the image out to all Gmail users. Unless you click on a link, marketers will have no idea the e-mail has been seen. Absurdly wrong, marketers already use a unique image URL for each email recipient, and Google has no way to know that all of those point to the same im…

If they wait until the user opens the email to cache the image, then it's actually BETTER for marketers. This essentially allows the marketer to track whether the email was opened by default.

> This essentially allows the marketer to track whether the email was opened by default.

And the spammer. Unless they decide to not load images by default from untrusted senders.

Re: Gmail blows up e-mail marketing by caching all images on Google servers

#33
post #12

> E-mail marketers will no longer be able to get any information from images—they will see a single request from Google, which will then be used to send the image out to all Gmail users. Unless you click on a link, marketers will have no idea the e-mail has been seen. Absurdly wrong, marketers already use a unique image URL for each email recipient, and Google has no way to know that all of those point to the same im…

it does, indeed, send the request when it is actually opened. see: https://news.ycombinator.com/item?id=6895876 /me goes to go find and turn on the "block third party images" feature.

Are we sure they won't programmatically/statistically detect these tracking URLs and start skipping the request after the first dozen or so retrievals out of 10,000,000?

Re: Gmail blows up e-mail marketing by caching all images on Google servers

#34
post #28
post #12

> E-mail marketers will no longer be able to get any information from images—they will see a single request from Google, which will then be used to send the image out to all Gmail users. Unless you click on a link, marketers will have no idea the e-mail has been seen. Absurdly wrong, marketers already use a unique image URL for each email recipient, and Google has no way to know that all of those point to the same im…

> Google has no way to know that all of those point to the same image. Try again. :)

Yeah, I am not sure where the original claim is coming from. It isn't that hard for Google to simply follow the links and compare the files as part of the caching process. So unless marketers start customizing the images in addition to the links, there isn't any reason why Google can't cache the images together.

And even if marketers do start customizing images, hasn't Google gotten pretty good at comparing very similar files? Isn't that how Google Music works without having a copy of every single individual upload?

Re: Gmail blows up e-mail marketing by caching all images on Google servers

#35
post #28
post #12

> E-mail marketers will no longer be able to get any information from images—they will see a single request from Google, which will then be used to send the image out to all Gmail users. Unless you click on a link, marketers will have no idea the e-mail has been seen. Absurdly wrong, marketers already use a unique image URL for each email recipient, and Google has no way to know that all of those point to the same im…

> Google has no way to know that all of those point to the same image. Try again. :)

Do you know more about this? Are they, say, MD5ing images that are served, or can this be circumvented by changing a pixel for each request?

Re: Gmail blows up e-mail marketing by caching all images on Google servers

#36
post #28
post #12

> E-mail marketers will no longer be able to get any information from images—they will see a single request from Google, which will then be used to send the image out to all Gmail users. Unless you click on a link, marketers will have no idea the e-mail has been seen. Absurdly wrong, marketers already use a unique image URL for each email recipient, and Google has no way to know that all of those point to the same im…

> Google has no way to know that all of those point to the same image. Try again. :)

[deleted]

Re: Gmail blows up e-mail marketing by caching all images on Google servers

#37
post #28
post #12

> E-mail marketers will no longer be able to get any information from images—they will see a single request from Google, which will then be used to send the image out to all Gmail users. Unless you click on a link, marketers will have no idea the e-mail has been seen. Absurdly wrong, marketers already use a unique image URL for each email recipient, and Google has no way to know that all of those point to the same im…

> Google has no way to know that all of those point to the same image. Try again. :)

... before making the requests. And then it's too late.

(Also, they might not actually point to the same image, it's very easy to make the images themselves unique if required.)

Re: Gmail blows up e-mail marketing by caching all images on Google servers

#38
post #19

There seems to be a lot of misinformation flying around. Here's [0] Google's support doc that clears up some of it. The most important part is at the end: "In some cases, senders may be able to know whether an individual has opened a message with unique image links. As always, Gmail scans every message for suspicious content and if Gmail considers a sender or message potentially suspicious, images won’t be displayed…

These two statements of yours seem at odds with each other:

"The privacy and security protections are about preventing other information (like ip, browser headers, cookies) from leaking, rather than read notifications."

"If you care about maintaining your privacy, I would recommend disabling the new functionality."

Re: Gmail blows up e-mail marketing by caching all images on Google servers

#39
post #12

> E-mail marketers will no longer be able to get any information from images—they will see a single request from Google, which will then be used to send the image out to all Gmail users. Unless you click on a link, marketers will have no idea the e-mail has been seen. Absurdly wrong, marketers already use a unique image URL for each email recipient, and Google has no way to know that all of those point to the same im…

Google could retrieve and cache a random sample of the images and hash them. Then they could note which image links go to the same images. And they could identify image links by noting that a bunch of emails have the same structure except for one image link that's different for every recipient.

So I think they actually could take a pretty good stab a deduping images with unique tracking URLs. It might not be perfect, but even if it works 95% of the time they could still kill the profitability of the unique tracking image technique.

Re: Gmail blows up e-mail marketing by caching all images on Google servers

#40
post #28
post #12

> E-mail marketers will no longer be able to get any information from images—they will see a single request from Google, which will then be used to send the image out to all Gmail users. Unless you click on a link, marketers will have no idea the e-mail has been seen. Absurdly wrong, marketers already use a unique image URL for each email recipient, and Google has no way to know that all of those point to the same im…

> Google has no way to know that all of those point to the same image. Try again. :)

Well of course it has a way. It can fetch the image. Then it will see it's the same - but now that means that the mail is 'reported' as delivered, possibly before the person receiving it has ever opened the message. This is an issue both for individuals (I don't want this information reported) and marketers (false positives).
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