ResourcesIoT Glossary Filter by topic Filter by Sector Consumer Energy & Utilities Health ISPs & MSPs IT & Enterprise OEM/Industrial 4.0 Public Sector Retail Smart City Transport and Logistics eUICC & eSIM 5G NB-IoT LTE-M IoT Connectivity IoT Security SIMPro Mapping Sunset IoT Glossary What is an M2M SIM Card?M2M SIM cards enable devices to perform actions and exchange information without the need for human input. IoT Glossary What is eUICC?Embedded UICC (eUICC) is a specific type of UICC that enables a single SIM to host multiple profiles. IoT Glossary What is IMSI?An IMSI (International Mobile Subscriber Identifier) is a string of digits that forms an important part of a SIM profile. Learn more here. IoT Glossary What is a MSISDN?Mobile Station Integrated Services Digital Network (MSISDN) is crucial in ensuring secure connectivity between IoT components. IoT Glossary What is GPRS?General Packet Radio Service (GPRS) is an evolved second-generation cellular network protocol. IoT Glossary What is GSM?Global System for Mobile Communication (GSM) is the technology behind 2G networks. IoT Glossary What is a HLR?Home Location Register (HLR) is a database for managing subscribers on 2G & 3G networks. IoT Glossary What is HSDPA?High Speed Downlink Packet Access (HSDPA) boosted what’s possible on the 3G network. IoT Glossary What are SIM cards?SIM cards are essential for a number of industries, including transport and logistics. IoT Glossary What is 3G?3G was the third generation of mobile technology, and opened the door to data-intensive applications in a range of industries. IoT Glossary What is 4G?4G is the fourth generation of mobile telecommunications technology, and it opened the doors to a number of solutions, including IoT focussed variants such as LTE Cat M, LTE Cat NB and LTE Cat 1. IoT Glossary What is Industry 4.0?Industry 4.0 is the fourth industrial revolution, and has given rise to the smart factory. IoT Glossary What are SIM form factors?SIMs are manufactured in a range of five standardised sizes, these are known as form factors. Find out more... IoT Glossary What is iSIM?An integrated SIM (iSIM), is when the SIM operating system is incorporated directly onto a device’s permanent computing hardware. IoT Glossary What is a multi-SIM?Multi-SIM technology makes it much easier to achieve constant connectivity and for devices to switch between regional operators. IoT Glossary What is LTE connectivity?Long-Term Evolution (LTE) is a 4G wireless broadband standard, designed to make it easier to deploy IoT and M2M devices efficiently. IoT Glossary What is SD-WAN?A software-defined wide area network is a method of architecture that creates a virtualised network overlay connected to a central one.