INSTALLATION
Overview
These instructions describe steps you should complete in the shop prior to field installation, and
field installation steps that are specific to the SpeedNet Radio.
Pre-Installation
Checklist
Before you install the SpeedNet Radio, carry out the following steps. This is best done in the shop
before you leave for the installation site.
1. Choose a location
.
The SpeedNet Radio should be securely mounted.
For remote antenna installations, S & C recommends lightning protection.
2. Plan your network.
SpeedNet Radio can be used in a wide variety of network configurations. Planning your
network in advance is recommended. You can develop a logical IP addressing scheme for
your particular application. Depending on your type of network, several factors may
influence your planning:
•
Point-to-point vs. mesh vs. Point-to-Multi Point
•
Standalone Network Connection
Once the network topology is determined, the SpeedNet Radios can be configured
appropriately.
IP Setup
AODV
SpeedNet Radios use a proprietary AODV (Ad-hoc On demand Distance Vector) routing system,
that works dynamically to maintain message routing. New routes are established with a route
request/route reply query cycle. When a source node needs to contact a destination that is not
stored in its route lookup table, it broadcasts a route request (RREQ) packet across the network.
Nodes receiving this packet update their information for the source node and create reverse
pointers to the source node in their route tables. If a receiving node is either the destination node or
has stored a route to the destination with a corresponding sequence number greater than or equal to
that contained in the RREQ, it will send a route reply (RREP) to the source node. Otherwise, it
rebroadcasts the RREQ. Nodes keep track of the RREQ’s source IP address and broadcast ID. If
they receive a RREQ that has already been processed, they discard the RREQ and do not forward
the packet. As the RREP propagates back to the source, nodes create forward pointers to the
destination. Upon receiving the RREP, the source node will begin forwarding data to the
destination. If the source node later receives a RREP containing a greater sequence number or the
same sequence number with a smaller hop count, it may update its routing information for that
destination and use the better route.
A route is maintained as long as it remains active, and is considered active when data
periodically travels that route. When the source stops sending data packets, the route will time out,
and eventually be deleted from the destination and intermediate node routing tables. If a link
breakage occurs while the route is active, the node upstream of the break propagates a route error
(RERR) message to the source node, informing it of the now unreachable destination(s). After
receiving an RERR, the source node can reinitiate route discovery, if the route is still required. The
received signal strength (RSSI) and number of hops required by the path are also recorded in the
lookup table, and these are considered when a node selects a route from its lookup table.
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CAUTION
