1 There is another obscure way of tracking users without using cookies or even Javascript.
2 So when the browser has the image and knows the checksum, it can send it to the webserver for verification.
3 This might be an okay alternative to disabling caching; you can only be tracked during your visit, and they can already do that anyway by following ..
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@sjoonk: 쿠키 대신 ETag를 사용한 사용자 트래킹 방법. http://t.co/OKytCVE0TN