Ever have this happen? You search for something and Google gives you a nice synopsis of exactly what you are looking for and a link and you follow the link and immediately hit a paywall? I was looking for "28nm gate capacitance" out of curiosity. Google gives this synopsis:
[PDF] 24.7 A High-Performance, High-Density 28nm eDRAM ... - IEEE Xplore
ieeexplore.ieee.org/iel5/6123666/6131464/06131608.pdf
Metal-Insulator-Metal (MIM) capacitor and integrated into. 28nm High-K Metal Gate (HKMG) logic technology. This. eDRAM memory features an HKMG CMOS ...
When you follow the link:
http://ieeexplore.ieee.org/iel5/6123666/6131464/06131608.pdfAn immediate paywall. And the words above are not even hidden in the HTML. How did Google read the PDF in order to index it properly?
I don't know, but I bet the web server is giving up the content if it thinks you are Google. But unless it is going off of known IPs, the only way to know what is at the end of an HTTP connection is by the headers, which can be anything you want them to be.
Hmmm.....