Introduction

We are entering an era where it is not inconceivable that every electronic device that we know of and use today may be networked and controlled remotely. Efforts to this effect have been given a shot in the arm with the imminent introduction of IPv6, which has enough addresses to cover every gadget that exists today and more.

The Embedded Web Server is especially suited to embedded Internet appliances and offers easy connectivity to any network via an Ethernet™ or dial-up Modem connection. Our goal is to provide an Internet-enabled device that can be accessed remotely over a network, through which an operator sitting on a remote computer terminal can monitor and control other connected equipment. Such a device may find applications in office and industrial automation, high-speed gaming and medical science, to name a few.

An Embedded Web Server is a microprocessor- or microcontroller-based embedded system that contains an Internet software suite as well as application code for monitoring and controlling external systems. Such a system can serve web pages over a TCP/IP network, allowing any browser with access to the network the ability to control and monitor devices connected to the Embedded Web Server.

In to the figure above, an industrial plant motor is being controlled via the Embedded Web Server over the Internet by an operator sitting in a remotely situated control room.



The following are some of the advantages of our Embedded Web Server:

  • Simplifies software and communications – The Embedded Web Server contains dynamic web pages that allow the operator to control and manipulate the embedded device over a TCP/IP-based network. This methodology provides a standardized communication mechanism for all embedded devices. In addition, the use of web pages simplifies software installation and maintenance on the server side, while providing a universal Graphical User Interface (GUI) through a web browser on the client side.
  • Offers increased functionality – Web-based GUIs offer a tremendous advantage over traditional control and monitoring systems where the system’s GUI software is running on the operator’s computer system itself. Unlike these traditional systems which are OS-specific and need installation, a web-based GUI is platform independent and needs no installation at the operator’s end. It is also very easy to use and require minimum operator training. Both static and dynamic pages can be created. Dynamic pages are interactive and can accept inputs from an operator and provide feedback on the system’s status. A login mechanism can be added for security purposes.
  • Simplifies system management – Web pages can be used to monitor, control and update the Embedded Web Server system. Any authorized user can access the system through a browser on a client to conduct maintenance, change system settings, and update system software.

The following are some terms you will encounter frequently in this document:

  • GUI – Graphical User Interface
  • HTTP – Hyper Text Transfer Protocol
  • HTML – Hyper Text Markup Language
  • DNS – Domain Naming System
  • CGI – Common Gateway Interface
  • MIME – Multipurpose Internet Mail Extensions

To be able to fully understand the contents of this document, you also need to have a brief understanding of how the Internet works, as well as a reasonable knowledge of TCP/IP, HTTP, HTML, Operating System fundamentals and multitasking. A concise introduction to each of these is given here for your convenience.