IoT connectivity glossary
Each term is defined in a few sentences, with the standard or document it comes from, then explained in the terms of an IoT project: what it changes for your devices, your SIMs and your data. The terms are grouped in six themes, from the identifiers printed on a SIM to the protocols that let software and AI agents manage a fleet.
Identifiers and numbers
- EID (eUICC Identifier)
- ICCID (Integrated Circuit Card Identifier)
- IMEI (International Mobile Equipment Identity)
- IMSI (International Mobile Subscriber Identity)
- MCC and MNC (Mobile Country Code, Mobile Network Code)
- MSISDN
- PLMN (Public Land Mobile Network)
SIM, eUICC and eSIM
- eIM (eSIM IoT remote Manager)
- eSIM
- eSIM profile
- eUICC (embedded Universal Integrated Circuit Card)
- IPA (IoT Profile Assistant)
- LPA (Local Profile Assistant)
- MFF2 (Machine Form Factor 2)
- Multi-IMSI SIM
- OTA (over the air) SIM management
- SGP.02 (eSIM for M2M)
- SGP.22 (consumer eSIM)
- SGP.32 (eSIM IoT specification)
- SIM Application Toolkit (STK)
- SIM form factors (2FF, 3FF, 4FF)
- SIM PIN and PUK
- SM-DP+ (Subscription Manager Data Preparation plus)
- SM-SR (Subscription Manager Secure Routing)
- UICC (Universal Integrated Circuit Card)
- USIM (Universal Subscriber Identity Module)
Radio access: 2G to 5G and IoT technologies
- 5G RedCap (Reduced Capability)
- 5G standalone (SA) and non-standalone (NSA)
- Coverage enhancement (LTE-M and NB-IoT)
- CSFB (Circuit-Switched Fallback)
- eDRX (extended Discontinuous Reception)
- GSM, GPRS and EDGE (2G)
- LTE Cat-1
- LTE Cat-1bis
- LTE Cat-4
- LTE frequency bands
- LTE-M (LTE Cat-M1)
- NB-IoT (Narrowband IoT)
- PSM (Power Saving Mode)
- RSRP, RSRQ and SINR (LTE signal quality)
- UMTS and HSPA (3G)
- VoLTE (Voice over LTE)
Mobile core network and roaming
- 5G core (5GC)
- APN (Access Point Name)
- Diameter
- EPC (Evolved Packet Core)
- Forbidden PLMN list (FPLMN)
- GGSN (Gateway GPRS Support Node)
- GRX (GPRS Roaming Exchange)
- GTP (GPRS Tunnelling Protocol)
- Home routing (home-routed roaming)
- HSS (Home Subscriber Server)
- IPX (IP eXchange)
- Local breakout
- MME (Mobility Management Entity)
- MVNO (Mobile Virtual Network Operator)
- Network slicing
- PDP context
- PDU session
- Permanent roaming
- PGW (PDN Gateway)
- Roaming
- SMS (Short Message Service)
- Steering of roaming
- UPF (User Plane Function)
IP addressing and private delivery
- ASN (Autonomous System Number)
- BGP (Border Gateway Protocol)
- CGNAT (Carrier-grade NAT)
- Cloud interconnection
- Cross-connect
- GRE (Generic Routing Encapsulation)
- IPsec
- IPv6 on cellular IoT
- MPLS (Multiprotocol Label Switching)
- MTU (Maximum Transmission Unit)
- NAT (Network Address Translation)
- Private IP address (RFC 1918)
- Public IP address
- RADIUS
- Static IP address (fixed IP on a SIM)
- VLAN (IEEE 802.1Q)
- VPC (Virtual Private Cloud)
- VRF (Virtual Routing and Forwarding)