Viconics VWG-50 (Classic ZigBee) Design Consideration and Setup Guide - Manual (Page 6)

6 | VWG-50-Setup Guide
A
BOUT
V
ICONICS
W
IRELESS
M
ESH
N
ETWORKS
The Viconics Wireless Gateway (VWG) and related wireless controller family
(VT7xxxXxxxxW) networkable devices operate using Zigbee™ ™/IEEE 802.15.4 physical
layer for communication.
General characteristics of the wireless physical communication layer are:
 Uses a wireless physical layer of 2.4GHz with a data rates of 250 kbps
 Yields high throughput and low latency
 Automatic multiple topologies configuration: star, peer-to-peer, mesh
 Fully handshake protocol for transfer reliability
 Range: 50 feet / 15M typical (up to 100 feet / 30 M based on environment)
IEEE 802.15.4 along with Zigbee™ ™’s Network and Application Support Layer
provide:

 Low cost installation deployment
 Ease of implementation
 Reliable data transfer
 Short range operation
 Very low power consumption
 Appropriate levels of security
The VWG acts as network coordinator device for the IEEE 802.15.4/Zigbee™ network
used with the Viconics wireless controllers.
Many network specific features of the IEEE 802.15.4 standard are not covered in detail in
this paper. However, these are necessary for the efficient operation of a Zigbee™
network. These features of the network physical layer include receiver energy detection,
link quality indication and clear channel assessment. Both contention-based and
contention-free channel access methods are supported with a maximum packet size of
128 bytes, which includes a variable payload up to 104 bytes. Also employed are 64-bit
IEEE and 16-bit short addressing, supporting over 65,000 nodes per network. All those
properties of the physical layer are used and employed by the Viconics mesh network but
are hidden to the installed / user for ease of configuration and commissioning of the
network database.