Starret DataSure, Руководство оператора

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DataSure™ Operators Manual 7 PT 6*****
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EndNode
An EndNode is a radio which links a tool to the wireless network. EndNodes connect
into the tool’s data port in the same way that conventional wired cables do. Use the
pushbutton on the EndNode to send tool data. There are two status indicators on the
EndNode; one is green and the other is red (refer to Appendix B for instruction of
their meanings). When not in use, turn the EndNode off via the sliding power switch
to conserve battery life.
1.5 Network Elements and Topologies
Starrett’s EndNodes, Routers, and Gateways together form what is termed a wireless mesh
network. The mesh network topology is a robust approach to covering large areas with radio
connectivity. The robustness offered by the mesh network topology cannot be equaled by any of
the other common network topologies. In a mesh network, the reach or range can be extended,
redundancy added, and the general reliability of the network enhanced by simply adding more
routers. This may be needed to provide a “best route” for the radio signal, thereby increasing
throughput and reducing congestion. All routers in a mesh network can communicate with two or
more other routers. Thus, a mesh network is very robust in terms of reliability and redundancy. If
one radio/network node can no longer operate, all the rest can still communicate with each other,
directly or through one or more intermediate nodes. This precludes the practicality of point-to-
point or daisy chain network approaches. The latter has single point of failure. If one router in
this configuration ceases to function, then there is no capability for the network to recover.
Additionally, the data to be sent will never reach its destination. Mesh networks “self-heal” in
that if interference enters the environment, such as a strong and localized plume of RF noise, the
network has alternate paths for the data to traverse and therefore can reach its intended
destination.
Wireless network layouts vary depending on a wide variety of purposes, structural, geographical
and environmental conditions. Users may have a variety of needs from their wireless data
collection system, such as robustness and assured reliability, while others need many end-nodes
supported and added radio coverage in terms of range or reach.
1.5.1 Routing Network - MESH
Mesh networks work best when arranged in a cluster which inherently allow for multiple and
redundant links to be established between routers, thereby providing best penetration within
common geographical areas. This would normally be the case in an area such as a large milling
operation where measurements are taken in work cells spread around the area. Additionally, in
QA inspector roles where the inspector roams the shop floor, radio coverage offered by the
MESH allows autonomous EndNode sensor or measurement connectivity with the network while
within range of the nearest router. The MESH is the most robust of network topologies in that
there are many paths for the radio signals to traverse in the event of EMI or mechanical
interference.
1.5.2 Routing Network - STRING
Networks consisting of routers in a common line or ‘string’ dramatically increase radio range,
but at the cost of loosing redundancy or alternate link paths between the network routers.