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Jon_Strabala_46's avatar
Jon_Strabala_46
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Feb 03, 2010

How to use HTTP::respond to send a 1x1 gif

Hello, I am trying to write a simple iRule to that uses HTTP::respond (from HTTP_REQUEST) to send a 1x1 gif back to the client on any request. I build a 1x1 gif (44 bytes) bu...
application delivery
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Jon_Strabala_46's avatar
Jon_Strabala_46
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Feb 04, 2010
There are a few uses

 

 

1

 

 

The 1x1 gif can be used as a web beacon (injected into all response content) this results in Google Analytics style information being sent to the ISP that uses the F5. Imaging that you only want to track a a single user or a subset of subset of users. Having the F5 short circuit the beacon request by injecting a 1x1 gif (without the request hitting the beacon server) effectively turns off tracking tracking. This allows selective tracking to meet the needs of Communications Assistance to Law Enforcement Act (CALEA)

 

 

2

 

 

Use the 1x1 gif request to perform authentication (sideband style) once the connection/session is authenticated, have the F5 short circuit the beacon request by injecting a 1x1 gif. This limits the load on the sideband auth server

 

 

- Jon