RACOM RipEX2, Руководство пользователя

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Example of a route from FEP (RipEX2 50) to RTU 2:
• The destination address is 192.168.2.2
• The routing table of the RipEX2 50 contains this record:
Destination 192.168.2.0/24 Gateway 10.10.10.1
• Based on this record, all packets with addresses in the range from 192.168.2.1 to 192.168.2.254
are routed to 10.10.10.1
• Because RipEX2 50’s radio IP is 10.10.10.50/24, the router can tell that the IP 10.10.10.1 belongs
to the radio channel and sends the packet to that address over the radio channel
• The packet is received by RipEX2 1 with the address 10.10.10.1 where it enters the router
• The routing table of RipEX2 1 contains the record:
Destination 192.168.2.0/24 Gateway 10.10.10.2
based on which the packet is routed to 10.10.10.2 over the radio channel
• The packet is received by RipEX2 2
• The router compares the destination IP 192.168.2.2 with its own Ethernet address 192.168.2.1/24
and determines that the packet’s destination is within its ETH network and sends the packet over
the Ethernet interface – eventually, the packet is received by RTU 2.
5.2.2.3. Addressing hints
In large and complex networks with numerous repeaters, individual routing tables may become long
and difficult to comprehend. To keep the routing tables simple, the addressing scheme should follow
the layout of the radio network.
More specifically, every group of IP addresses of devices (both RipEX2's and SCADA), which is accessed
via a repeater, should fall in a range which can be defined by a mask and no address defined by that
mask exists in different part of the network.
A typical network consisting of a single centre and number of remotes has got a tree-like layout, which
can be easily followed by the addressing scheme – see the example in the Figure "Optimised addressing"
below.
RipEX2 Radio modem & Router – © RACOM s.r.o. 50
RipEX2 in detail