LonWorks Protocol

A technology initiated by the Echelon Corporation in 1990, the LonWorks provides a platform for the for building industrial, transportation, home automation and public utility control networks to communicate with each other. Built on the Local Operating Network, it uses the LonTalk protocol, in order to have a peer to peer communication with each other, with out actually having a gateway or other hardware.

LonWorks is a protocol developed by Echelon Corporation for manufacturers who wish to use an open protocol with off-the-shelf chips, operating systems, and parts to build products that feature improved reliability, flexibility, system cost, and performance. LonWorks technology is accelerating the trend away from proprietary control schemes and centralized systems by providing interoperability, robust technology, faster development, and scale economies.

A major goal of LonWorks is to give developers, from the same or different companies, the ability to design products that will be able to interact with one another. The LonWorks protocol provides a common applications framework that ensures interoperability using powerful concepts called network variables and Standard Network Variable Types (SNVTs).

Communication between nodes on a network takes place using the network variables that are defined in each node. The product developer defines the network variables when the application program is created as part of the Application layer of the protocol. Network variables are shared by multiple nodes.

The use of Standard Network Variable Types (SNVTs) contributes to the interoperability of LONWORKS products from different manufacturers. If all manufacturers use this variable type in their application when a network variable for continuous level is defined, any device reading a continuous level can communicate with other devices on the network that may be using the variable as a sensor output to initiate an actuator.

· LonWorks Requires an Isolated Transceiver Design. Understanding the different supported communication channels, how to use the Echelon Transceivers and creating a noise immune design can challenge the novice LonWorks designer.

· The LonWorks protocol can be complex. LonWorks network variables (SNVTs) are a unique way to transfer data among nodes. Understanding what SNVTs to support and how to implement them come with many surprises, especially if you start "cold" from the documentation.

· The Neuron Processors Support a Distinctive OS. The OS is tightly integrated into NodeBuilder, the software development tool, the Neuron Processors, the LonWorks protocol and the transfer of SNVTs around the network. Understanding all these components and how they work together requires significant effort.