The following diagram illustrates how an external client request is handled in an Enterprise Gateway configuration:

External clients send requests to Enterprise Gateway Server (1). Enterprise Gateway Server collects client information from each request and evaluates the request against any Enterprise Gateway rules that have been defined. Enterprise Gateway Server then passes requests that have not violated a rule to the Internal Server (2). The Internal Server processes the requests and sends responses to Enterprise Gateway Server (3). Enterprise Gateway Server then passes the responses back to the client (4).