A computer implemented method, apparatus, and computer program product for generating cookies. A cookie value is retrieved in response to receiving the request. An expiration for the cookie value is set based on a time period in which the request is received. A set of unique identifiers, including the expiration, are added to the cookie value and a cookie name to form a cookie. A response to the request is sent to an intermediate server. The response includes data responsive to the request and the cookie. The validity of the data for the response is related to the expiration.