• The Pieces You Need
• LonTalk Protocol
• Neuron Chips
• LonWorks FAQ
• Download the Reference Implementation
• Introduction to the LonWorks Platform eTraining

The LonWorks Platform: Technology Overview

The solution for control networks.

Today's networks range in size from two to 32,000 devices and are used in everything from supermarkets to petroleum plants, aircraft to railway cars, fusion lasers to slot machines, and single-family homes to skyscrapers. Almost every industry is moving away from proprietary control schemes and centralized systems. Manufacturers are using open, off-the-shelf chips, operating systems, and parts to build products that feature improved reliability, flexibility, system cost, and performance.

LonWorks technology is accelerating this trend by providing interoperability, robust technology, faster development, and scale economies.

The LonWorks Protocol

Devices in a LonWorks network communicate through the LonWorks protocol. This provides a set of services that lets a device's application program send and receive messages to and from other network devices—without needing to know the network topology or the other devices' names, addresses, or functions.

The LonWorks protocol can optionally provide end-to-end acknowledgement of messages, authentication of messages, and priority delivery to provide bounded transaction times. Support for network management services lets remote network management tools interact with devices over the network, so they can:

• reconfigure network addresses and parameters
• download application programs
• report network problems
• start/stop/reset device application programs

The LonWorks protocol, and thus LonWorks networks, can be implemented over basically any medium, including power line, twisted pair, radio frequency (RF), infrared (IR), coaxial cable and fiber optics.

P2P Architecture

While there are many ways to build control networks, a flat, peer-to-peer (P2P) architecture is the best method. In P2P, no single “master” on the network determines if a message from one device should be sent to another, nor determines in what order messages should be sent. Instead, control devices are free to communicate directly with each other; this reduces bottlenecks and prevents the systemwide failures that can occur when the master fails. As a result, P2P-based control networks offer high reliability and high performance.

What's the LonWorks platform?

LonWorks is the name of our control networking technology platform. It’s called a platform because it comprises the following elements:

• Communications protocol. This protocol is the underlying technology of a LonWorks control network. An international standard, it’s known as ANSI/EIA709.1, SEMI E56.6, IEEE 1493-L, EN14908, and others.
• Dedicated microprocessor. Invented by Echelon, this processor (also known as the Neuron chip) is highly optimized for devices on a control network. Neuron chips have three 8-bit inline processors: two are dedicated to the communications protocol and one is a general-purpose applications processor. A number of chip manufacturers market the Neuron family of microprocessors.
• Transceivers. These components transmit the protocol on a specific media, such as twisted-pair or power line. All devices on a control network must have a transceiver. Our twisted-pair and power line signaling technology have been approved as ANSI/EIA709.3 and 709.2, respectively. Both are also expected to be included in EN14908.
• Network database. Called the LNS Network Operating System, this database is the required software component of open control systems; it ensures an open environment for extending, maintaining, and managing LonWorks based systems. The network operating system serves critical functions in a control network. LNS also supports a plug-in architecture.
• Internet connectivity. The standardized applications (called LonMark profiles) and Standard Network Variable Types (SNVTs) of a LonWorks network pass through Internet connectivity devices via Web services (SOAP calls in XML format). Accessing and controlling LonWorks networks via Web services—an international IT standard—lets them become integral parts of enterprise applications, services centers, and more.
• Interoperability. Interoperability means that devices created by different manufacturers can work together without needing a gateway to translate data from one device to another. A single, standardized software tool—LonMaker for Windows—manages and installs such disparate devices. Interoperability in the LonWorks world is governed by the LonMark International Group, which maintains interoperability guidelines, creates standard applications, and tests and certifies products.