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Wireless Network Planning
It is generally expected that the user / installer has
substantial knowledge of wireless networking whereby
they fully understand wireless topology, component
capabilities and system-wide organization. To ensure
complete system integrity, the Chromalox specified
core components must be properly employed and wire-
less network design best practices must be followed.
Chromalox will not be held responsible otherwise.
For support, Chromalox provides optional professional
startup and commissioning services as well as the fol-
lowing wireless sensing information and guidelines:
Wireless Network Topology
When it comes to industrial wireless sensor networks
(WSN), two types of topologies, (or the way wireless
components interact with each other), exist: Infra-
structure and Ad hoc. Each has their own strengths
and limitations.
In the Infrastructure or Star topology, there is one cen-
tral coordinator, typically a hub (or switch). In this to-
pology, the sensor devices communicate via the hub
rather than directly with each other as shown in Figure
A below. Communication rates are relatively high while
complexity, reliability and distances between compo-
nents are relatively low.
In an Ad hoc or Mesh topology, however, all devices are
capable of communicating with all other devices within
radio range, creating the topology shown in Figure B.
The benefits of this topology include increased reliabil-
ity and the distance between components whereas la-
tency and complexity becomes greater.
It is also possible to have a hybrid topology called Star-
Mesh, in which there is a combination of both Mesh
and Star topologies such as in Figure C.
In reality, most Industrial Sensor Networks combine
internal wired and wireless topologies, which employ
routers, gateways and firewalls with external Mesh to-
pologies that are comprised of multiple bi-directional
wireless sensors tied to a common wireless gateway.
See the Site Installation Guidelines for component
considerations within a Mesh or Ad hoc wireless sen-
sor network.
One Direction O
Star
Figure A
Mesh
Figure B
Star-Mesh
Figure C
Bi-Directional
One Direction
& Bi-Directional