RACOM M!DGE2, Руководство пользователя

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3. Implementation notes
3.1. Ethernet SCADA protocols
SCADA equipment with an Ethernet protocol behaves as standard Ethernet equipment from a commu-
nications perspective. Thus the communication goes transparently through the cellular network. The
implementation requires heightened caution to IP addressing and routing. NAPT functionality should
be used frequently.
3.2. Serial SCADA protocols
A SCADA serial protocol typically uses simple 8 or 16 bit addressing. The mobile network address
scheme is an IP network, where range is defined by the service provider (sometimes including individual
addresses, even in the case of a private APN). Consequently, a mechanism of translation between
SCADA and the IP addresses is required. To make matters worse, IP addresses may be assigned to
GPRS (EDGE, UMTS, etc.) devices dynamically upon each connection.
Please read application note "M!DGE/MG102i - Serial SCADA Protocols"
1
which describes how to ef-
ficiently solve this problem using RACOM routers.
3.3. Network center
In every network, the center plays a key role and has to be designed according to customer's require-
ments. Several possible solutions are described in the application note
"M!DGE/MG102i - Typical us-
age"
2
.
3.4. VPN tunnels
Customer data security arriving through the mobile network is often very important. Private APN is the
basic security requirement, but not safe enough for such applications.
VPN tunnels solution is closely connected with the center and is also described in application note
"M!DGE/MG102i - VPN Configuration"
3
.
1
http://www.racom.eu/eng/products/m/midge/app/scada.html
2
http://www.racom.eu/eng/products/m/midge/app/midge-mg102i_centre.html
3
http://www.racom.eu/eng/products/m/midge/app/VPN_config.html
11 © RACOM s.r.o. – M!DGE2 GPRS/UMTS/HSPA+/LTE router
Implementation notes