Technical FAQ

SGP.22 is the GSMA's technical specification for consumer eSIM Remote SIM Provisioning. It defines the architecture, interfaces, security requirements, and operational procedures for managing eSIM profiles in consumer devices including smartphones, tablets, and wearables. The specification covers the SM-DP+ server, the Local Profile Assistant (LPA) on the device, and the eUICC hardware.

An eUICC (embedded Universal Integrated Circuit Card) is a secure element permanently integrated into a device's circuit board. Unlike a removable SIM card that stores a single carrier profile, an eUICC can store multiple operator profiles simultaneously and switch between them under software control. The eUICC contains a secure operating system and cryptographic capabilities that protect stored profiles.

When you purchase an eSIM plan, the provider's SM-DP+ server creates an encrypted profile package containing your carrier credentials. When you scan the QR code or use the provider's app, your device's LPA initiates a secure connection to the SM-DP+ server, authenticates the transaction, and downloads the encrypted profile to the eUICC. The profile is decrypted and installed within the secure element.

Key European LTE bands include Band 1 (2100 MHz), Band 3 (1800 MHz), Band 7 (2600 MHz), Band 8 (900 MHz), and Band 20 (800 MHz). Band 20 is particularly important for rural coverage. For 5G, Band n78 (3.5 GHz) is the primary mid-band used across Europe. Travelers with older devices should verify their device's band support against destination country requirements.

Network steering refers to the mechanisms by which an eSIM provider directs a device to connect to preferred network partners rather than simply the strongest available signal. Providers configure preferred roaming lists (PRLs) that prioritize specific networks. Poor network steering configuration can result in a device connecting to a lower-quality network even when better options are available.

IPX (IP Packet Exchange) is the interconnection framework used for international mobile roaming. When you use your home carrier's SIM in a foreign country, your data traffic is routed through IPX networks back to your home carrier's infrastructure before reaching the internet. This adds latency compared to direct local network access, which is one reason why local SIM cards and eSIM plans often provide better performance than traditional roaming.

EU roaming regulations require that carriers provide roaming services at domestic rates, but they do not mandate specific technical quality levels. In practice, roaming connections may use different network configurations than domestic connections, potentially resulting in different speed caps or quality-of-service parameters. The regulations focus on pricing rather than technical performance standards.

LTE-Advanced (LTE-A) is an enhancement to the base LTE standard that introduces carrier aggregation (combining multiple frequency bands for higher speeds), enhanced MIMO (multiple antenna techniques), and other performance improvements. Most modern smartphones support LTE-A, but the actual performance benefit depends on whether the network in the visited country has deployed LTE-A features.

eSIM support requires both hardware (eUICC chip) and software (LPA implementation) components. Some Android manufacturers ship devices with eUICC hardware but do not implement the LPA software, or implement it only for specific carrier partnerships. Additionally, carrier-customized Android devices may have eSIM functionality disabled by the carrier. The Android eSIM ecosystem is less standardized than Apple's implementation.

The number of eSIM profiles a device can store depends on the eUICC memory capacity, which varies by manufacturer and model. Most consumer devices can store between 5 and 20 profiles, though only one (or two on dual-eSIM devices) can be active simultaneously. The GSMA specification does not mandate a minimum storage capacity, so this varies significantly between devices.

eSIM profile transfer between devices is technically possible under the GSMA specification but is controlled by the carrier/provider policy. Many providers allow profile transfer when upgrading to a new device, but the process requires interaction with the provider's SM-DP+ server. Some providers restrict transfers for security or commercial reasons. Always check provider policy before assuming transfer is possible.

The GSMA SGP.22 specification mandates end-to-end encryption for profile delivery using asymmetric cryptography. The eUICC contains a unique certificate that is used to authenticate the device to the SM-DP+ server, and profile packages are encrypted specifically for the target eUICC. This architecture makes profile interception or cloning technically very difficult when implemented correctly by a GSMA-certified provider.

Travel eSIM providers collect data about your device, usage patterns, and location (through network connection data). This data may be subject to the privacy laws of the country where the provider is based, which may differ from your home country's privacy protections. Reviewing the provider's privacy policy before purchase is advisable, particularly for travelers with heightened privacy requirements.

Travel eSIM services from reputable providers offer the same baseline security as any cellular connection. The cellular layer itself is encrypted. For sensitive work communications, the primary security consideration is the application layer — using end-to-end encrypted messaging and VPN services for sensitive data transmission is advisable regardless of the connectivity method used.

Systematic troubleshooting steps: (1) Verify the eSIM profile is installed and enabled in device settings. (2) Toggle airplane mode off/on to force network re-registration. (3) Check that the correct eSIM is set as the data SIM. (4) Try manually selecting a network in cellular settings. (5) Verify you're in a covered area according to the provider's coverage map. (6) Restart the device. (7) Contact provider support with your EID and ICCID numbers ready.

Data-only plans provide internet connectivity without a phone number or voice call capability. Data+voice plans include a local phone number and support for traditional voice calls and SMS. For most travelers, data-only plans are sufficient as voice calls can be made over the internet using VoIP applications. Data+voice plans are more appropriate for travelers who need a local number for receiving calls or SMS verification codes.

Most travel eSIM plans implement a two-tier data model: a high-speed allowance (e.g., 10GB at 4G speeds) followed by reduced-speed access (typically 128–512 Kbps) for the remainder of the validity period. The throttling is implemented at the network level by the provider's network partner. At throttled speeds, basic messaging and browsing remain functional, but video streaming and large file transfers become impractical.

Most travel eSIM plans support mobile hotspot (tethering) functionality, but policies vary. Some plans count hotspot data at the same rate as direct device data, while others apply different rates or restrictions. Check your specific plan's terms. Note that using your device as a hotspot significantly increases battery drain and may affect the thermal performance of your device during extended use.

Pre-travel checklist: (1) Verify your device supports eSIM and is carrier-unlocked. (2) Purchase and install your eSIM plan 24-48 hours before departure. (3) Verify the profile appears in your device's cellular settings. (4) Test connectivity in your home country if possible (some plans activate immediately). (5) Note your provider's customer support contact information. (6) Download offline maps and content as a backup. (7) Ensure your device's software is up to date.