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eSIM Glossary
A clear and concise reference for the technical terms you'll encounter in the eSIM world.
Basic Concepts
1 terms
- eSIM— A digital SIM card embedded in your device.
- eSIM (Embedded SIM) is a digital SIM card technology that is embedded in your phone at the factory and can be programmed with software. It replaces the traditional plastic SIM card; it's activated remotely and doesn't require physical insertion or removal. Multiple eSIM profiles can be installed on the same device, but only one can be active at a time.
Identifiers
2 terms
- EID— The 32-digit unique identification number of the eSIM chip in your device.
- The EID (Embedded Identity Document) is a 32-digit numerical code unique to each eSIM-compatible device, permanently written during manufacturing. Your carrier or eSIM provider uses this code to prepare a profile for you. You can find your device's EID in Settings → About Phone; if an EID field is present, your device supports eSIM.
- ICCID— The 19-22 digit unique number of a single SIM/eSIM profile.
- The ICCID (Integrated Circuit Card Identifier) is the number that uniquely identifies a SIM card or an eSIM profile. Each eSIM plan you purchase has its own unique ICCID; line activation and usage tracking are done through this number. You can see the ICCID in your SIM settings or on the eSIM details screen.
Infrastructure
1 terms
- SM-DP+— The server that securely delivers the eSIM profile to your device.
- SM-DP+ (Subscription Manager — Data Preparation+) is the backend server that prepares and securely delivers the eSIM profile to your device. When you scan the QR code, your device connects to this address and downloads the profile over an encrypted channel. This ensures the profile is installed only on your device and cannot be transferred to another.
Activation
3 terms
- QR Kod— The QR code that lets you install your eSIM profile on your device in a single step.
- The QR code provided upon order completion contains the location of your eSIM profile on the SM-DP+ server. When you scan this code with your phone's camera, the device automatically downloads the profile and starts the installation. You can only use the QR code once; to install it again, you must request a new code.
- Manuel Kurulum— Installation with an SM-DP+ address and code instead of a QR code.
- If your device doesn't have camera access or you can't scan the QR code, you can also install your eSIM profile manually. To do this, simply enter the provided SM-DP+ address (server) and activation code (matching ID) on the Settings → Cellular → Add eSIM screen.
- Aktivasyon— The process of installing an eSIM profile and making it ready for use.
- Activation consists of two steps: installation (loading the profile onto the device) and activation (the line starting to work). For most travel eSIMs, the plan's validity period begins when the line connects to a network for the first time, so it's recommended to install it just before your trip.
Dual SIM
2 terms
- DSDS— Using two SIM lines on the same device simultaneously.
- DSDS (Dual SIM Dual Standby) refers to the mode that allows two lines to be on standby at the same time on one device. You can use your local line (a physical SIM or an eSIM) for your primary phone number and a second eSIM for mobile data. If you are on a call on one line, an incoming call on the other will be shown as busy.
- DSDA— Using two lines actively at the same time (both are active).
- DSDA (Dual SIM Dual Active), unlike DSDS, is a more advanced mode where both lines are active simultaneously. Not all devices support this; most eSIM-compatible phones operate in DSDS mode.
Connection Settings
1 terms
- APN— The gateway your mobile data uses to connect to the internet.
- APN (Access Point Name) is the gateway setting that allows a mobile device to connect to the internet via the cellular network. The APN is usually configured automatically when the eSIM profile is installed; manual setup is rarely needed. If mobile data isn't working, you can check the value specified by your eSIM provider in Settings → Cellular → APN.
Coverage
2 terms
- Roaming— Connecting through another carrier's network when outside your home network.
- Roaming is the automatic connection to a foreign carrier's network, with which your home provider has an agreement, when you are abroad. Travel eSIMs also use roaming in the background, but the pricing structure is different from traditional telecom roaming—the package price is fixed, and there are no surprise bills.
- Kapsama / Coverage— The countries and carriers where the plan is valid.
- Each eSIM plan is valid in specific countries and on specific carrier networks within those countries. Regional plans (Europe, Asia, Global) work in multiple countries, while country-specific plans are only active in that single country. It's important to check the list of countries and carriers covered by the plan before purchasing.
Product
1 terms
- Veri Paketi— A mobile data allowance for a specific amount and duration.
- A data plan refers to a mobile data quota that you can use within a specified amount (e.g., 1 GB, 5 GB, 20 GB) and duration (e.g., 7 days, 30 days). The validity period may start from the moment the plan is activated or from the first data usage; this is specified at the time of purchase.
Top-up
1 terms
- Veri Sıfırlama / Topping Up— Adding a new plan to your existing eSIM line.
- Top-up means adding new data before your plan expires or refilling the same eSIM line after it runs out. Providers may allow adding another plan to the same line based on the user's usage habits.
Sharing
1 terms
- Kişisel Erişim Noktası— Sharing your mobile data with other devices as a Wi-Fi hotspot.
- Personal hotspot (or tethering) allows you to share your phone's mobile data with a tablet, laptop, or another phone. eSIM plans support this feature; however, it consumes data from your plan's allowance, and some providers may restrict sharing.
Network Technology
1 terms
- 5G Desteği— Whether the plan can provide a connection at 5G speeds.
- 5G support depends on three conditions: your device must be 5G-compatible, the eSIM plan must include 5G access, and a 5G network must be available in your area. If these three conditions are not met, the connection will be made via 4G/LTE; the data plan can still be used, but the speed will be limited.
Usage
1 terms
- Veri Aşımı / Fair Use— Data is cut off when the plan runs out; no surprise extra charges.
- With travel eSIM plans, mobile data is automatically cut off when your included allowance is used up; you won't face high overage charges like with traditional telecom lines. To continue, you need to buy a new plan or top-up your existing line.
Management
1 terms
- Profil Silme— Removing an eSIM line from the device.
- Deleting an eSIM profile from your device is an irreversible action. A deleted profile cannot be reinstalled; you must request a new QR code for the same plan from the provider. When switching from an old phone to a new one, it's recommended to request a new download on the new device before deleting the profile from the old one.
Device Change
1 terms
- eSIM Transfer (iPhone)— Transferring an eSIM from an old iPhone to a new one.
- Apple offers an eSIM transfer feature via Bluetooth on iOS 16 and later. When setting up your new iPhone, you can wirelessly transfer your lines using the "Transfer eSIM from a nearby iPhone" option. For providers that do not support this feature, you will still need to request a new QR code.
Service Type
1 terms
- Veri Yöntemi (Data-only)— A plan that provides only mobile data — no calls/SMS.
- Most travel eSIMs are "data-only": they provide only mobile internet and do not include traditional calling and SMS services. Voice/video apps that work over the internet, like WhatsApp, Telegram, and FaceTime, will work without issues. If a local phone number is required, an additional service or a local SIM card is needed.
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