Specialized terminology and acronyms dominate the mobile technology sector. Since eSIM was developed within this context, newcomers might find it challenging to grasp. This glossary serves as a quick-start guide to fundamental concepts and definitions.
Core eSIM Concepts #
eSIM (Embedded Subscriber Identity Module)
A digital SIM that allows you to activate a cellular plan from your carrier without needing a physical SIM card. The “e” stands for embedded, meaning it’s built directly into your device.
eUICC (embedded Universal Integrated Circuit Card)
The technical term for the hardware component that enables eSIM functionality. It allows the remote and/or local management of Profiles in a secure way. UICC is the software component of a SIM card, based on a Tamper Resistant Element (see TRE).
eSIM Profile
Network description files managed and held by device manufacturers, containing details on how to set up a connection and work with a given supplier. These are matched to the SIM by the device.
It enables access to a cellular network and influences some aspects of the device behavior on the cellular network.
RSP (Remote SIM Provisioning)
The downloading, installing, enabling, disabling, and deleting of a Profile on an eUICC. Secure and remote (over the air) management of network operator profiles on an eSIM or iSIM.
Some eSIM providers use third-party RSP so may charge eSIM profile cost for the transaction charges by their RSP provider while on eSIM Access plans most of the time the profile charges are waived off.
Connectivity & Network Terms #
APN (Access Point Name)
A parameter that must be configured for mobile internet access. It determines the network access method used by the phone to connect to the internet.
It offers the information your phone uses to connect with your carrier’s network. It lists the address your phone uses to connect to the network, the ports used to handle Multimedia Messaging Service (MMS) messages, the type of data that particular APN uses, and other pieces of information to make sure your phone works correctly.
Most of eSIM Access data plans are auto-apn, in case it doesn’t work, please offer end users the APN information for using the eSIM: https://esimaccess.com/docs/what-is-apn-in-esim/
Roaming
Using cellular service outside of the home network coverage area. The subscriber will be allowed to use a roaming partner’s network.
So to use an eSIM, make sure the step of “turn on roaming” is set up unless it’s eSIM from MNOs.
Breakout IP
Breakout IP refers to the public IP address used by a network (like an ISP or Mobile Carrier) as the source address for traffic originating from its users when that traffic is routed onto the public internet.
Some social APPs may require nonhkip for better access which could be found in eSIM Access platform, but be aware that if eSIM could be used to access specific website or APP may depending on user location and social app own policy, so we can’t guarantee 100% success rates. Additionally, some websites or applications may be blocked in certain countries or regions due to government censorship or other reasons.
LTE (Long Term Evolution)
A standard for 4G wireless broadband technology that offers increased network capacity and speed to mobile device users. LTE offers higher peak data transfer rates — up to 100 Mbps downstream and 30 Mbps upstream.
Carrier File (KI, OPC etc)
Network description files containing details on how to set up a connection and work with a given supplier. These are matched to the SIM by the device.
In an eSIM’s carrier file, KI (Key) and OPC (Operator Code) are critical security credentials for authenticating a device to a mobile network. These cryptographic keys are included in the digital eSIM profile that the carrier provides to your device during activation.
eSIM Access is the orginal eSIM profile creators taking carrier files and translates them into eSIM profiles, instead of just reselling eSIMs.
MSISDN (Mobile Station International Subscriber Directory Number)
The full mobile number including the country code and any prefixes.The MSISDN, or Mobile Station International Subscriber Directory Number, is the standard phone number that identifies a mobile subscription on a network, allowing calls and texts to be routed correctly. It’s the number you give out to others, consisting of a country code, a national destination code (or area code), and a unique subscriber number.
eSIM Access currently offers eSIM data only without Voice and SMS.
VoLTE (Voice over LTE)
Voice calls over a 4G LTE network. eSIM Access currently offers eSIM data only without Voice and SMS.
PIN
Four digit access code for a SIM
PUK (Personal Unlocking Key)
Used to unlock a mobile phone. May be needed if
- your device is locked to a particular carrier
- you enter the PIN incorrectly three times
CDR
A line-by-line record of a SIM’s activity including call start/end, caller ID, recipient ID, Call type, Service type, Call charges and device info.
Network supported in each region:
The supported eSIM network coverage depends on the OPLMN selected for the profile. Based on partner requirements, we can adjust the OPLMN to alternative options and provide premium connectivity services when needed.
PLMN (Public Land Mobile Network)
HPLMN (Home PLMN): The PLMN to which the user belongs.
RPLMN (Registered PLMN): The PLMN where the device is currently registered. It is the preferred PLMN.
OPLMN (Operator PLMN): A list of PLMNs provided by the operator, representing optional networks.FPLMN
(Forbidden PLMN): PLMNs that are prohibited from being accessed.
Data Plan Types #
Daypass Plans / Unlimited Data Plans
An eSIM data plan that allows users to consume a specific amount of high-speed data per day. After the high-speed quota is exhausted, users can continue to use unlimited data at 2G speeds. For example, a 5-day plan covering 30+ European regions with 500MB per day provides users with 500MB of high-speed data (4G/LTE/5G) daily, usable in any covered country, with daily reset. The validity period typically ranges from 1 to 365 days, and billing is calculated by multiplying the number of days by the plan cost.
Check eSIM Access Daypass / Unlimited Data plans
Data in Total (Fixed Data Plans)
An eSIM plan with a fixed data quota, allowing users to consume a predetermined total amount of high-speed data within a specific validity period (e.g., 7 days, 30 days, 60 days, 90 days). Once the data is fully utilized, users must purchase additional data or face speed restrictions. Examples of such plans include options like 1GB, 3GB, 5GB, or 10GB offered by some providers.
eSIM Access has single /multi-area plans of 「Data in Total 」plans with comprehensive skus and may offer customized plans after evaluating the demand and request is reasonable.
Fair Usage Policy (FUP) / (Throttle down to 128kbps/256kbps/384kbps/512kbps/1mbps/2mbps etc)
Telecom operators implement this policy to maintain overall network quality and prevent certain users from excessively or prolonged using network resources. When users consume large amounts of network resources beyond fair usage limits within a short period, operators may reduce their speeds to ensure other users receive reasonable network connectivity quality. FUP helps control infrastructure costs, prevent unauthorized usage, and provide equitable services.
eSIM Access could offer different daypass/daily plans with different FUP policies, and may allow customization of the FUP policy according to partner demand.
Identification & Security #
eSIM functions the same as SIM card and completes the process like the way you visit the physical store and subscribe to a carrier with the SIM card, the authentication process of using eSIM is digitalized, in a secure way onto the devices if working with eSIM API providers with in-house RSP following the GSMA specifiation.
ICCID (Integrated Circuit Card Identifier)
A number assigned to the SIM hardware. A SIM card is essentially an integrated circuit board that is programmed by the mobile operator (MNO or MVNO). The golden part of the SIM is the chipset that the ICCID number is assigned to.
eSIM Access partners can access ICCID in API/Console all the time to identify the eSIM card that’s turned on on end user’s device.
IMSI Number (International Mobile Subscriber Identity)
The telecom company assigns a unique number assigned to the SIM card that they issue to their subscribers. The IMSI numbers are usually 15 digits long (not always though) and can be used to find the subscriber’s country and mobile network, among other SIM-related details. It is tied to the SIM card rather than the phone itself.
eSIM Access partners can consistently retrieve IMSI information via API or console. This unique identifier enables key functions such as data top-ups, validity extensions for prepaid plans, and real-time monitoring of eSIM data usage on the carrier platform. The relevant IMSI data and usage status can also be seamlessly delivered to partners through webhooks and API interfaces.
IMEI Number (International Mobile Equipment Identity)
The telecom company assigns a unique number assigned to the SIM card that they issue to their subscribers. The IMSI numbers are usually 15 digits long (not always though) and can be used to find the subscriber’s country and mobile network, among other SIM-related details. It is tied to the SIM card rather than the phone itself.
EID (Embedded Universal Integrated Circuit Card Identifier)
The eUICC identifier is used in the context of remote provisioning and management of the eUICC.
Service Management #
SM-DP+ (Subscription Manager Data Preparation Protocol+)
The SM-DP+ address is a unique identifier that specifies the address of the subscription management server used to activate an eSIM. The activation code is a one-time code sent by the service provider, that enables the eSIM to be activated on the device.
eSIM Access offers the whole lifecycle of SM-DP+ status ( operational status of eSIM cards only, this process typically requires users to manually perform actions such as entering activation codes, scanning QR codes, or toggling the eSIM on/off directly on their eUICC-enabled devices.) Learn more at: https://esimaccess.com/docs/what-does-each-esim-status-mean/
OTA (Over-The-Air)
A wireless technology used to communicate with a SIM card, download applications to a SIM card, and manage a SIM card.
OTA (Local Profile Assistan)
An eSIM LPA (Local Profile Assistant) is the software component on a device that manages eSIM profiles, enabling users to download, install, enable, disable, and delete carrier services without a physical SIM card. It acts as a bridge between the device’s eUICC chip and a remote server (SM-DP+) to facilitate remote SIM provisioning (RSP), allowing for seamless switching and management of mobile network operator subscriptions.
OTA Keys
The credentials included in the profile used in conjunction with OTA platforms.
Confirmation Code
A code entered by an End User required by the SM-DP+ provider to confirm the download of a Profile.
Multi-IMSI (Multiple International Mobile Subscriber Identities)
Multi-IMSI technology allows the profiles of multiple MNOs to be stored on a single SIM. With multi-IMSI, you often have a single primary MNO.
Business & Organizational Terms #
MNO (Mobile Network Operator):
Mobile network operators, traditional operators, own their own base stations and operator licenses.
MVNO (Mobile Virtual Network Operator):
Mobile Virtual Network Operator (MVNO): A virtual mobile network operator leases the MNO’s network infrastructure and other resources to develop its own user base. Based on the core network components of the operator, MVNOs are categorized as Full MVNOs, Light MVNOs, and Branded Resellers.
GSMA (Global System for Mobile Association):
GSMA facilitates protocols and standards in mobile technology, from 4G and 5G, to 6G and beyond.
GSMA develops and issues the definitive specifications for eSIM and eUICC, including those related to Remote SIM Provisioning (RSP) like the SGP.22 (Consumer RSP) and SGP.31/ SGP.32(IoT RSP) series, to ensure global interoperability and security for these technologies. These specifications provide the technical foundation for how profiles are securely downloaded and managed on an embedded SIM (eSIM) integrated into a universal integrated circuit card (eUICC), enabling remote management of subscriptions over the air.
eSIM Access is a GSMA-certified provider that operates its own fully compliant RSP platform and deploys data centers in Germany and the Netherlands.
eSIM Carriers
Apple maintains a comprehensive list of recognized eSIM carriers on its official support page. This list includes major eSIM providers across various countries, covering a range of travel and business solutions. Notable examples include B2C travel eSIM providers like Airalo and Holafly, B2B whitelabel solutions such as eSIM Access, and B2B aggregators like Redtea Mobile (parent company of eSIM Access, listed as recognized worldwide eSIM carrier on Apple’s website as well ) that specialize in IoT and automotive applications. These aggregators collaborate with multiple MNOs and MVNOs worldwide to offer extensive connectivity options.