SCADA equipment with an Ethernet protocol behaves as standard Ethernet equipment from a communications 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.
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” which describes how to efficiently solve this problem using RACOM routers.
In every network, the center plays a key role and has to be designed according to customer’s requirements. Several possible solutions are described in the application note “M!DGE/MG102i – Typical usage”.
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”.