NSAPI is used to handle Hypertext Transfer Protocol transactions in the Netscape Enterprise Server's request-response process through its built-in Server Application Functions (SAF). Netscape Server's SAFs are written with the NSAPI and are functions called by the server to deal with requests received from a client. At start up, after initialization, the server waits for an HTTP request from the client for a resource such as an HTML file, a CGI program, or an image file, for example. The request consists of a Universal Resource Identifier (URI), an HTTP method, and, sometimes, information about the client or the request. The request-response process involves a sequence of six steps:
1. AuthTrans, which verifies request information (name and password, for example);
2. NameTrans, which translates the in the request into a local file system path;
3. PathCheck, which checks the validity of the path and the authorization of the user for path access;
4. ObjectType, which determines the MIME (Multi-purpose Internet Mail Encoding) type of the resource requested by the client;
5. Service, which is the response to the client; and finally,
6. AddLog, which adds related entries to the log file.
Each step may involve multiple operations, which are performed by Server Application Functions (SAF). Each SAF returns a result code to the server to indicate the success or failure of the operation. Based on the result code, the server either proceeds to the next step, carries out the next SAF in the current step, or aborts the process.