Great Reasons to Web Enable a Device

Incorporating an embedded web server is a remarkably powerful mechanism for easily implementing a variety of key features and functions in your device.

A user sitting at any standard browser sees a web enabled device as a web site.  The device presents itself and its state graphically and responds to buttons, hot links, and the entire array of familiar browser controls. The potential for this kind of interface is essentially unlimited.

Although the word "server" is often associated with things that are heavyweight, web servers can actually be implemented efficiently and in a small footprint.  For example, TargetWeb^TM adds only approximately 30 KB of code and 30 KB of data to the application.  It is the web client, the browser, that is the large and sophisticated component of the client/server pair, having to parse the HTML and render the graphic output.  Fortunately, there is no need to incorporate the browser code when web enabling a device.

Consider the advantages of incorporating a web server into an embedded device: 

Eliminate Implementing Both Target and Host Software to Interface to Your Device

External monitoring and control of embedded devices has traditionally been done in one of three ways: (1) front panel, (2) dumb console interface, or (3) custom protocol connected to a client program running on a computer.  All of these methods require special purpose programming on the target to support their operation in addition to the code that actually implements the desired activity.  For example, the console interface requires at least rudimentary parsing of text input and formatting of text output. Because of the effort involved and footprint constraints, interfaces to devices were often pared down from what would have been considered ideal.

Front panel and console interfaces are inherently primitive, but the client program method carries the additional burden of the implementation of the client program on a host computer, usually a Windows system. Not only does this involve a lot of effort, but also it is typically outside of the expertise of embedded developers. Another disadvantage of this approach is the need to install the client program on any computer to be used as a controlling host system.

Web enabling devices provides a new method of interfacing to devices that requires essentially no target side programming and works with universally available, standard client software.

Universal Availability of Clients

Any standard browser can be used on a computer to interface to your device. Automatically your device interfaces to Windows, Linux, Solaris, and the Macintosh.  Client software to interface to your device is already installed everywhere and everyone knows how to use it.

Remote or Local Access

A web enabled device can be accessed anywhere in the world if it is connected to the Internet or can be locally connected on a LAN with equal ease. Remote management and running field diagnostics can be done from literally anywhere and, because the data transfer is guaranteed to be error free, remote field upgrades can be done reliably. Eliminate completely issues relating to overseas dial-up, transmission speed dependencies, and custom protocols or cabling used to connect to your device. 

Easily Create Graphic User Interface

It is a lot of work to implement a graphical user interface for a non web enabled embedded device. In contrast, extremely user friendly and good looking interfaces are very easy to create and maintain for web enabled devices.  Target side resource demands for these interfaces are very light, consisting of just the HTML pages in text format.

Leverage Commercially Available Web Design Tools

Use advanced web content design tools, such as Macromedia HomeSite or Microsoft FrontPage, to design and debug user interfaces on desktop computers before embedding the pages on your target.

Easy to Maintain and Enhance Interface to Target

By simply uploading new web pages to the target, the interface can be maintained and enhanced.  In web enabled devices, the user interface is data, not code. Although it would be possible to custom write an application specific user interface engine which was data driven, incorporating an embedded web server provides this functionality as a standard, commercially available component.

Uses Universally Accepted, Standard Communication Protocol

Instead of starting out with a blank sheet of paper and designing your own protocol for remote device monitoring and control, use the established, powerful, and universally available HTTP standard protocol.

In summary, it makes sense to web enable just about any device that either needs or could benefit from a nontrivial user, monitoring, or control external interface, possibly even at the cost of adding an otherwise unneeded network port.  Now-a-days networking hardware is quite inexpensive and can often be incorporated by simply selecting a CPU variant that has integrated Ethernet (e.g. the Motorola MCF5282 ColdFire).  Certainly, for any device already having a TCP/IP port, this approach is strongly indicated.