How to Understand the Settings on your SIM
Inside of your physical SIM or eSIM profile, there are various small applications and files that influence how your device connects to the cellular networks. There are the standard elementary files (EFs) found on all SIMs that you can read or written to via common AT Commands. There are also resources specific to Super SIM,such as our multi-IMSI applet. Each of these may impact how a SIM behaves. We'll refer to this collection of files and applications on the SIM as the SIM's "settings".
From time to time, SIMs will be manufactured with updated settings in order to:
- give you access to more networks or new radio technologies
- route data through different downstream connectivity partners to deliver an improved experience or reduced rates that we can pass onto you
- fix configuration issues on the SIM
Updating Existing SIMs Over-the-Air
Existing SIMs will be updated over-the-air (OTA) to deliver a consistent experience across your SIMs regardless of when they were originally manufactured. Your SIM will automatically open a separate data connection to check for and download updates. Learn more about over-the-air updates.
A SIM will have one or more Settings Packages installed on it at any given time. All SIMs will have a version of
base-settings installed on them. Additional Settings Packages may be applied in addition to the
base-settings to deliver different customized experiences by overriding some portion of the configuration in the
Each Settings Package has a version and generally follow semantic versioning. When changes are made to a Settings Package, a new version is released.
Each Settings Package may have dedicated documentation explaining how the experience may have changed from version to version. For example, see the documentation for the
base-settings Settings Package.
Viewing a SIM's Settings and Updates
You can use the SettingsUpdates API to determine what Settings Packages are currently installed on a SIM and if there are any outstanding over-the-air (OTA) updates waiting for your SIMs.
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