Specifications

11 / 80
The private IP addresses are typically used in M2M GW's LAN, in VPN peer IPs and in Arctic's
LAN. To avoid overlapping the network address space (thus causing possible routing problems), it
is a good practice to use different class of private IP addresses for each set of addresses.
In this example (see Figure 6: Scenario 1, M2M GW connected with public IP address) the M2M
GW LAN network’s
IP address is 192.168.0.0 and netmask is 255.255.255.0. This is also
represented as 192.168.0.0/24, since the 255.255.255.0 netmask is 24-bit. The 24-bit netmask (C
class network) is chosen for the example as it is easy to understand.
The LAN address of Arctic is 10.10.10.0/24 and the VPN peer addresses are chosen from
172.16.0.0 address space.
Note: In order to avoid routing problems, it is important that the VPN peer IP addresses are not
overlapping the existing IP addresses in the system.
See Appendix A: IP v.4 addressing for more details on IP addressing.
7.1. Scenario 1, M2M GW connected with public IP address
In a simple setup, there is only one public, routable IP address needed; The M2M GW's IP
address. In this scenario, the M2M GW is connected directly to Internet with one public IP address
via its eth0 interface. (See page 15, chapter 10, Connecting and cabling the units for more
information). The Arctics are using the cellular operator’s public access point to connect to the
internet.
Below is an example network plan:
Figure 6: Scenario 1, M2M GW connected with public IP address
Entity IP address Netmask
M2M LAN 192.168.0.0 255.255.255.0
M2M LAN IP (eth1) 192.168.0.1 255.255.255.0
SCADA computer 192.168.0.2 255.255.255.0
VPN peer addresses
M2M: 172.16.0.1
Arctic: 172.16.0.2
Point-to-point
M2M WAN IP (eth0) Public, not shown N/A
Arctic LAN 10.10.10.0 255.255.255.0
Arctic LAN IP 10.10.10.1 255.255.255.0
Ethernet device 10.10.10.2 255.255.255.0
Arctic GPRS IP Dynamic, not shown N/A