Linux has made a major impact with embedded systems, and a wide range of applications can be considered computer appliances. Developers sometimes turn to Linux providers for development tools and operating system support. Regardless of whether you take this approach or roll your own, there’s a lot more to getting a sophisticated application up-and-running than tools and an operating system.
This is where Linux Appliance Design comes in, presenting middleware that provides a framework for a network-based appliances including interfaces via Web, display, front panel, SNMP, and command line. A bootable Linux CD includes all the necessary software to construct what is presented in the book.
One of the examples is Laddie, a Linux-based alarm system, based on the ladd daemon that provides central coordination between the application, the user interface, and logging support. Laddie is not something to build a product with, but it can be built upon. Likewise, the framework presents important details like SNMP support and system security well. The approach uses the latest technologies including XML and AJAX so be prepared to cover a lot of ground.
While most of the book addresses architecture and configuration, there’s plenty of C code as well. This makes the presentation ideal for more sophisticated embedded developers, even those already familiar with Linux.
Probably the greatest benefit of the book is its breadth. It delves into the details that designers and programmers will relish without glossing over large swaths of middleware necessary for a robust appliance solution.
If you’ve built appliances already, you’ll probably pick up a few tips. Otherwise, this book will be invaluable for those new to Linux appliances. Some knowledge of Linux and C will be extremely helpful in appreciating the presented technology.