CASTRUM eSIM technology with Multiple IMSI for enhanced privacy, security, and global mobile connectivity.

Every SIM or eSIM card contains an IMSI (International Mobile Subscriber Identity), a unique number that reveals your mobile identity. The issue? The IMSI is always transmitted to the base station whenever your device connects to the network, allowing tracking, profiling, and surveillance — even when you are not actively using the internet. In the age of mass surveillance and aggressive data collection, this has become a critical vulnerability.

CASTRUM eSIM, combined with Multiple IMSI technology, provides users with a level of security and privacy that traditional operators simply cannot offer.

What is Multiple IMSI and Why Does It Matter?

Instead of relying on a single identity, your eSIM can contain multiple IMSI profiles. The device can dynamically switch between them depending on signal quality, security conditions, or location. This means:

  • Seamless connectivity – if one network fails, the phone automatically connects to another.
  • Reduced traceability – with identities rotating, passive tracking becomes nearly impossible.
  • Global freedom – multiple identities in one device enable smooth travel worldwide without changing SIM cards.

Real-Life Use Cases

  • Business traveler: flying from Europe to Asia, the phone seamlessly switches to the best local network without any interruption.
  • Journalist in a conflict zone: the device switches IMSI to a neutral operator while traffic is encrypted through WireGuard VPN, keeping identity hidden.
  • Digital nomad: works across countries without roaming surprises or loss of connectivity.