Mobile code and method for resource management for mobile code

A mobile code linked to a certificate including at least a resource requirements list (RRL) including those resources needed by the mobile code to be properly executable plus those resources that are known a priori to be accessed when executing the mobile code. The unique certificate contains additionally an issuer of the certificate information identifying the entity issuing the certificate, a subject information identifying the mobile code to which the certificate is referred, and a validity period information stating the period of time within which the certificate is valid. When downloading or uploading a mobile code the RRL is transferred to the user informing the user of the resource requirements of the mobile code. An execution environment is provided in an execution peer of the user, the execution environment defining at least the resource access policy that will be applied to the mobile code on execution.