Mapping Between User Interface Fields and Protocol Information

A gateway device coupled between a client device and a server, comprising:

• a mapping generator configured to generate a mapping that maps input fields within a web page to a byte range within a body of a test payload generated by the web page, the mapping generated in response to 1) identifying one or more format rules associated with the input fields, 2) submitting information within the input fields that satisfies the identified format rules, and 3) intercepting the test payload, the mapping generator further configured to store the generated mapping within a non-transitory computer-readable storage medium;
• a query processing device configured to, when the gateway device is configured to operate in a data protection mode, identify portions of a received payload corresponding to at least one of the input fields using the mapping;
• an encoding engine configured to encode one or more of the identified portions of the received payload to produce encoded data;
• and
• an output configured to output the encoded data to the server.