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Overview – Echelon FTXL User Manual

Page 14

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Introduction to FTXL

Overview

Automation solutions for buildings, homes, and industrial applications include
sensors, actuators, and control systems. A

L

ON

W

ORKS

network

is a peer-to-peer

network that uses an industry-standard control network protocol for monitoring

sensors, controlling actuators, communicating with devices, and managing
network operation. In short, a L

ON

W

ORKS

network provides communications and

complete access to control network data from any device in the network.
The communications protocol used for L

ON

W

ORKS

networks is the ANSI/CEA

709.1-B (EN14908.1) Control Network Protocol. This protocol is an international

standard seven-layer protocol that has been optimized for control applications
and is based on the Open Systems Interconnection (OSI) Basic Reference Model

(the OSI Model, ISO standard 7498-1). The OSI Model describes computer

network communications through the seven abstract layers described in Table 2.
The implementation of these layers in a L

ON

W

ORKS

device provides standardized

interconnectivity for devices within a L

ON

W

ORKS

network.

Table 2. L

ON

W

ORKS

Network Protocol Layers

OSI Layer

Purpose

Services Provided

7

Application

Application compatibility

Network configuration, self-installation,

network diagnostics, file transfer,
application configuration, application

specification, alarms, data logging,

scheduling

6

Presentation Data interpretation

Network variables, application messages,
foreign frame transmission

5

Session

Control

Request/response, authentication

4 Transport

End-to-end

communication reliability

Acknowledged and unacknowledged

message delivery, common ordering,
duplicate detection

3

Network

Destination addressing

Unicast and multicast addressing,
routers

2

Data Link

Media access and framing Framing, data encoding, CRC error

checking, predictive carrier sense

multiple access (CSMA), collision

avoidance, priority, collision detection

1

Physical

Electrical interconnect

Media-specific interfaces and modulation

schemes

Echelon’s implementation of the ANSI/CEA-709.1 Control Network Protocol is

called the

LonTalk protocol

. Echelon has implementations of the LonTalk

protocol in several product offerings, including the Neuron firmware (which is
included in a ShortStack

®

Micro Server), LNS

®

Server, LNS remote client,

i

.LON

®

servers, and the FTXL LonTalk protocol stack. This document refers to