Embedded networking

Networking is for computers. Its big and expensive and needs careful set-up and management.
That used to be the case, but as everybody now knows almost anything can connect to the network including your Iphone and Kindle. Home and industrial networks are everywhere.
Of course these manufacturers are big and can afford the cost of developing the extensive hardware and software needed to to make all this work. What about smaller companies who would also like to have networking in their products?

Surley its much too expensive both in additional cost in the product and in design and development cost?
In these pages I hope to show:

  • That networking can be included in almost any product at an affordable price.
  • It can be implemented in a reasonable time frame.
  • Can complement features possible with other types of communications.
  • Can add whole new functionality to the product.

So, Why do we want to add networking? Here are a few reasons:

  • It is a replacement for a range of legacy connection types including serial ports and even USB.
  • Networking is already built-in to all computers and it does not need special drivers or any software installation to work. (Compare that with writing and installing a USB driver and making it work.)
  • It is fast. At 100Mbits per second (or even 1000Mbits if really necessary) you can move large amounts of data easily.
  • Network cabling and switches are very cheap and easy to install. Many buildings are already fully networked.
  • Once on a network you have access to the Internet. That opens up many new ideas in monitoring and control.
  • Multiple services can be run across a single Ethernet port.
  • Last but not least, everybody else is doing it!

What does the 'Multiple Services' statement mean?

When you think about traditional communications, like a serial port, you think about one set of data going TOO the device and one set of data FROM. This forms a connection. Networking (and in particular TCP/IP) sees it rather differently. Although there is only a single piece of wire, there are a number of 'virtual' connections that run along it. Actually, there are up to approximately 65000 possible connections! They all exist at the same time and work apparently independently of each other. They don't even all go to the same computer. It is very possible to have a device that is talking to a local computer for control purposes and at the same time using a separate virtual connection to a different computer to record datalog information etc.