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920MHz Band Wireless Device (Korea) USERS MANUAL EM-9121 Rev. 1
3. EXAMINING WIRELESS NETWORK CONFIGURATION
3.1 MULTIHOP NETWORK
3.1.1 NETWORK PARTICIPATION AND ROUTE CONFIGURATION
A wireless multihop network can be configured with a parent device and multiple child devices.
Each child device obtains authentication from the parent device to join the network after startup, and communicates using its IPv6 address.
The IPv6 address is assigned automatically using the prefix set to the parent device and short addresses set individually to the par-
ent device and each child device.
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UPSREAM ROUTE
1) A child device collects information on the number of hops and the network quality (packet error rate) from adjacent parent and
child devices, and decides a preferential parent as a connection destination from a list of parent candidates selected from the
adjacent devices.
2) Based on the information, the upstream network route of the child device is generated.
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DOWNSTREAM ROUTE
1) The parent device registers the route transmitted from the child device in its route information table.
2) With this table, the parent device automatically generates the downstream network route (source routing) to the child device.
a
a
Generating upwstream route
Generating downstream route
Parent device
Parent device
Adjacent/
preferred
parent
Adjacent/
parent candidate
Adjacent/
parent candidate
(1) Collecting network quality
(2) Upstream route
Child device
(1)
(1)
(2)
(1)
Hop=0
Hop=1
Hop=1
Hop=2
Hop=2
Hop=3
Hop=0
Hop=1
Hop=1
Hop=2
Hop=2
Hop=3
Hop=3
Hop=3
Hop=2
e
g
h
i
f
d
b
c
Adjacent/
parent candidate
Adjacent/
parent candidate
Child device
(1) Transmitting route
(2) Downstream route
Hop=2
Adjacent/
preferred
parent
(1)
(2)
e
g
h
i
f
c
d
b
Figure 3.1 Wireless network
3.2 CONFIRMING COMPONENTS IN INSTALLATION ENVIRONMENT
Confirm the installation locations and the wiring destinations of a data acquisition device and remote I/Os in the installation environ-
ment of wireless devices.
3.3 CONFIRMING WIRELESS SECTIONS
Determine sections to be used for wireless communications in the installation environment.
Since a parent device is always connected to a data acquisition device, confirm also the connection of the parent device and remote
I/O child devices.
