Cookie encryption/decryption using iRule

Thanks for the quick replies, but I am still having a few issues. I am trying to concat "enc" onto the encrypted cookie string using this code in the Response:

 

 

set encrypted [HTTP::cookie encrypt mycookie cookiekey]

 

set newencrypted [concat "enc" $encrypted]

 

 

and in the Request, I am not sure how to check to see if the "enc" is in the string. Any ideas on which command to use? You suggested substr before, but I could not find any documentation on how to implement it. Thanks for your help!