Which url coding algorithm uses links in Google or Baidu

Question

when i search google

http://www.google.com/search?sclient=psy&hl=en&newwindow=1&site=&source=hp&q=shopping&btnG=Search#sclient=psy&hl=en&newwindow=1&source=hp&q=%E8%B4%AD%E7%89%A9&aq=f&aqi=&aql=&oq=&gs_rfai=&pbx=1&fp=d5a61cbe48a951c1

then you can see that in the "Ads" area there are two links, but go to the mouse pointer to these links:

http://www.google.com/aclk?sa=L&ai=**CYB017kwHTa7GIsT0rQeqnujiCbmK0tEB2dyc_RqQtLWLAQgAEAEoAlCl7byW______8BYJ250IGQBcgBAakCwbO8-f4qhD6qBBlP0FHICrzLP3Yh2d7vTjWYUE8AvmD9DoLL...

http://www.google.com/aclk?sa=L&ai=*CNCTz7kwHTa7GIsT0rQeqnujiCaTU7tsBvOyAshaQtLWLAQgAEAIoAlCe7aiK_P____8BYJ250IGQBcgBAakCwbO8-f4qhD6qBBlP0CHcKLzIP3Yh2cPyGSqYUE8AvmD9DoLL...

for a search engine in China, baidu also encodes ad links, so can anyone know which encoding algorithm they use to encode the urls of the ad links? thanks in advance.

Answer 1

These values ​​probably act as tokens attached to the URL in their back-end, and not as an encoded version of the URL itself. Thus, it would be impossible to translate these values ​​directly into a URL without querying their servers.