Private IP SIM Cards: Fixed Static IP for Remote Access and SCADA
A private IP SIM card is a SIM that provides a fixed, static IP address on a private Access Point Name (APN). Unlike a standard consumer SIM – where the IP address changes every time the device reconnects and the device sits behind carrier-grade NAT – a private IP SIM gives your router or connected device a permanent, known IP address that is reachable from authorised network locations at all times.
Why CGNAT Makes Standard SIMs Unsuitable for Remote Access
Carrier-grade NAT (CGNAT) is the technology mobile networks use to share a limited pool of public IP addresses across millions of customer devices. When your device is behind CGNAT:
- The IP address visible from the internet is shared with many other customers
- Inbound connections from the internet cannot reach your specific device
- The IP address changes every time the device reconnects to the network
- Port forwarding at the device level is ineffective because the public IP is not controlled by you
This makes standard SIM cards fundamentally unsuitable for applications where the remote system needs to initiate a connection to the device – SCADA polling, remote CCTV viewing, remote router management, and any server-type application running on the connected device.
How a Private IP SIM Solves This
A private IP SIM places your device on a private APN with a static IP address. From the perspective of your control centre, monitoring platform, or remote management system:
- The device always has the same IP address – no DDNS or dynamic DNS workarounds required
- The device is reachable by an inbound connection at any time
- The IP address can be whitelisted at the control centre or monitoring platform firewall for security
- The private APN can be extended to connect to your corporate network via a VPN or dedicated link, providing a secure private network overlay
Private APN vs Fixed IP on Public APN
Some providers offer a “fixed IP” SIM that provides a consistent public IP address without a private APN. This is better than a dynamic SIM but does not provide the security of a private APN – the device is still reachable from the public internet at large. A private APN routes traffic on a private network path that does not transit the public internet, meeting the security requirements of regulated industries (energy, utilities, healthcare, finance). SimWise can explain the difference and recommend the right option for your application.
Applications for Private IP SIM Cards
- Remote CCTV and NVR access – view cameras from any location without DDNS
- BESS and substation SCADA – DNP3 and Modbus polling from control centre to RTU
- Industrial IoT and telemetry – control centre polling of remote sensors and RTUs
- Retail and PoS remote management – central management of distributed site routers
- Remote router management – SSH and web access to router admin interfaces
- Remote desktop and VPN server access for field workers
Multi-Network Private IP SIMs
SimWise private IP SIMs are multi-network, roaming across EE, Vodafone, O2, and Three while maintaining the same static IP address. When the device switches to a different network (due to signal conditions), the private IP address and APN connectivity are maintained – the control centre continues to communicate with the device without interruption or reconfiguration. See also: multi-network IoT SIM cards.
Get a Private IP SIM Card
Tell us about your application and the IP address requirements – whether you need connectivity back to a central monitoring platform, what protocol is in use, and the geographic location of the device. We will supply a private IP SIM card pre-configured with your static IP and APN credentials.