Omron CS1W-ETN21 Creating Routing Tables, Routing Table Overview, Local Network Table

Creating Routing Tables Section 6-4

6-4 Creating Routing Tables

When the FINS communications service is used, routing tables must be cre- ated in advance. Routing tables are required in the following circumstances.

•When communicating with a PLC or computer on another network (e.g., remote programming or monitoring using FINS messages or a CX-Pro- grammer)

•When multiple Communications Units are mounted to a single PLC (i.e., CPU Unit).

•When routing tables are used for one or more other nodes on the same network.

It is not necessary to set routing tables if one Communications Unit is mounted to the PLC and the nodes are connected as one network. The rout- ing tables are required not only for nodes communicating via the FINS com- munications service but also for all relay nodes on the network.

6-4-1 Routing Table Overview

	The routing tables describe the transmission path for FINS messages when
	the FINS communications are used. It consists of two tables: A local network
	table and a relay network table.
Local Network Table	The local network table is a table describing the correspondences among unit
	numbers of the Communications Units and Boards mounted to each node.

Example

Unit #04

Unit #05

Unit #06

Unit #07

Network #1

Network #2

Network #3

Network #4

Local Network Table

Local network Unit number address

104

205

306

407

Note	1. The unit number is set (0 to F: 1 to 15) by the rotary switch on the front of
	the Ethernet Unit.
	2. The network address is the number of the network (1 to 127) to which the
	Communications Unit or Board is connected. It is set when the local net-
	work table is created.
Relay Network Table	A relay table is a table that shows the nodes to which data should be sent first
	in order to send data to a network that is not connected to the local node. It
	shows the correspondence between the address of the final destination net-
	work, and the network address and node address of the first relay point of the
	path to reach there. When internetwork communications are carried out, the
	end network can be reached by following the relay points.

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