eSIM Basics

What is an eSIM (embedded SIM)? An eSIM is a programmable SIM profile embedded in a device’s eUICC (embedded Universal Integrated Circuit Card). Unlike physical SIMs, eSIM profiles can be remotely provisioned, activated, updated and revoked over the air using GSMA Remote SIM Provisioning (RSP) flows. eSIMs support multiple profiles on the same device and enable instant carrier switching without physical SIM swaps.

Why eSIM matters for GeSIM

• Frictionless provisioning: instant activation via SM-DP+/RSP instead of shipping physical SIMs.

• Multiple profiles: one device can hold multiple operators; enables the Smart Network Switch.

• Better UX: no physical SIM handling, QR/activation tokens.

• Programmability: profiles + on-chain settlement enable pay-on-usage, microtransactions and automated settlement models.

Key terms

• eUICC: the hardware inside a device that securely stores eSIM profiles.

• Profile: an operator subscription package (operator credentials, keys, operator policy) that the eUICC installs.

• EID: eUICC identifier (device-specific). Treat as sensitive, store only hashed EID for No-KYC design.