Cellular and Wireless Carriers Industry Terminology

AAA (Authentication, Authorization, and Accounting)

A network framework and set of servers that validate subscriber identities, determine their permissions/policies, and track usage for charging and auditing in carrier networks.

Our AAA server authenticates the SIM’s IMSI before granting data access | Roaming sessions are authorized via inter-operator AAA | Accounting records from AAA feed the billing system

Access Point Name (APN)

A logical identifier that maps a device’s data connection to a specific packet data network or service profile (public internet, private enterprise network, IoT APN). Determines IP addressing, DNS, and policy.

Provision the IoT fleet on a private APN with static IPs | Wrong APN settings caused data sessions to fail | We charge a premium for secure corporate APNs

Average Revenue Per User (ARPU)

A financial KPI measuring the average monthly revenue generated per subscriber; used to benchmark monetization and segment profitability.

Postpaid ARPU rose after our 5G plan refresh | Bundling video increased ARPU by $2 | We target high-ARPU enterprise lines

Backhaul

The transport network that carries traffic between cell sites and the core (typically fiber, microwave, or mmWave links). Impacts capacity, latency, and reliability.

Microwave backhaul upgrades doubled rural site capacity | Fiber cuts degraded backhaul and triggered congestion | Backhaul is the bottleneck for our new FWA sites

Billing/Business Support Systems (BSS)

The software stack for product catalog, rating/charging, billing/invoicing, collections, customer care, and order management. Integrates with OSS and policy for real-time charging.

We migrated to converged BSS for prepaid and postpaid | BSS real-time charging underpins zero-rating offers | A catalog change in BSS launched our family plan

Carrier Aggregation (CA)

A radio technique that combines multiple spectrum carriers/bands to boost user throughput and capacity in LTE and 5G.

n78+n28 CA improved uplink coverage and DL speed | 3CC CA unlocked gigabit LTE in city centers | We prioritize CA for premium tiers

Churn

The percentage of subscribers who disconnect service over a period; a key metric for retention, loyalty, and lifetime value.

Postpaid churn fell to 0.8% after device promos | We run win-back offers to reduce prepaid churn | Network quality issues drove higher churn in Q2

Core Network

The control- and user-plane systems that manage mobility, session, policy, authentication, and interconnect (EPC for 4G, 5G Core for 5G).

Core upgrades enabled standalone 5G | Policy in the core enforces QoS tiers | We peer in the core for lower OTT latency

Customer Lifetime Value (CLV)

The discounted value of the expected profits from a subscriber over their tenure; central to acquisition and retention decisions.

High-CLV segments justify device subsidies | Reducing churn increased average CLV | We prioritize care for top-decile CLV customers

Dynamic Spectrum Sharing (DSS)

A feature allowing LTE and 5G NR to share the same spectrum dynamically, allocating resources based on traffic demand.

DSS accelerated our nationwide 5G coverage | We saw a slight LTE capacity hit after enabling DSS | DSS helps balance NR uptake during transition

eSIM (Embedded SIM)

A programmable SIM embedded in the device that supports remote provisioning of carrier profiles without a physical card.

Customers activate via eSIM QR code in minutes | eSIM simplifies global roaming for travelers | IoT sensors ship with operator eSIM profiles

Evolved Packet Core (EPC)

The 4G LTE core network architecture responsible for mobility, session management, and IP connectivity (e.g., MME, SGW/PGW).

VoLTE launched after EPC and IMS integration | EPC anchors NSA 5G deployments | We virtualized parts of the EPC to cut TCO

FDD/TDD (Frequency/Time Division Duplex)

Two duplexing methods: FDD uses paired spectrum for simultaneous uplink/downlink; TDD uses time slots on the same channel.

n41 TDD needs careful UL/DL ratio planning | Coverage is easier with low-band FDD | We aligned TDD frame configs to reduce interference

Fifth Generation (5G)

The latest cellular generation featuring NR radio, higher spectrum efficiency, massive MIMO, low latency, and support for slicing and IoT.

5G SA enabled VoNR and slicing trials | Mid-band 5G is our capacity workhorse | 5G FWA is a key growth vector

Fixed Wireless Access (FWA)

Broadband service to homes/businesses using 4G/5G radio instead of wired last-mile; relies on CPE devices and capacity planning.

We added 100k FWA subscribers this quarter | Beamforming improved FWA reliability | FWA fill-in leverages mmWave in dense areas

Frequency Band

A specific spectrum range (e.g., 700 MHz, 3.5 GHz, 28 GHz) licensed or shared for cellular use; affects coverage and capacity.

Low-band extended rural coverage | n78 mid-band carries most 5G traffic | Guard bands protect adjacent services

gNodeB (gNB)

A 5G base station implementing the NR air interface and interfacing to the 5G Core; supports features like massive MIMO and beamforming.

We swapped older radios for gNBs with 64T64R | SA requires gNB support for new interfaces | gNB software upgrade enabled carrier aggregation

Handover

The process of transferring an active call or data session from one cell/site to another as a user moves, maintaining service continuity.

Inter-frequency handovers dropped due to tuning | VoLTE handovers between macro and small cells | Optimizing handover margins reduced call drops

IMS (IP Multimedia Subsystem)

A standards-based architecture for delivering IP voice, video, and messaging services (e.g., VoLTE/VoNR/VoWiFi) with policy and charging.

IMS core is prerequisite for VoLTE | VoNR rollout required IMS upgrades | We onboard MVNO voice via hosted IMS

Internet of Things (IoT)

Connected devices and sensors using cellular (LTE-M, NB-IoT, 5G) for telemetry, control, and analytics across industries.

We sell managed IoT with private APNs | NB-IoT suits long battery life meters | IoT ARPUs are low but margins are high

KPI (Key Performance Indicator)

Quantitative measures used to track network, commercial, and service performance (e.g., latency, call setup success, churn).

We review weekly RAN KPIs by market | NPS and churn are our headline KPIs | SLA commits map to specific KPIs

Latency

The round-trip delay experienced by packets; critical for UX, gaming, voice, and industrial control.

SA 5G shaved latency below 20 ms | Backhaul congestion increased latency spikes | We market low-latency plans for gamers

Long Term Evolution (LTE)

The 4G radio technology and ecosystem preceding 5G; supports CA, VoLTE, and high spectral efficiency.

Gigabit LTE relies on 3CC CA and 256-QAM | LTE remains the coverage anchor in rural | VoLTE stabilized before 5G launch

Massive MIMO

Large antenna arrays enabling spatial multiplexing and precise beamforming to boost capacity and coverage, especially in 5G mid-band.

64T64R massive MIMO doubled sector throughput | Beam tracking improved cell-edge rates | Hardware weight drove tower loading checks

Mobile Network Operator (MNO)

A facilities-based carrier that owns/operates spectrum and network infrastructure and sells services directly and wholesale.

MNOs lease tower space from TowerCos | Our MNO hosts several MVNOs | Regulators cap MNO spectrum holdings

Mobile Virtual Network Operator (MVNO)

A provider that sells mobile services using another operator’s network under wholesale agreements; may own BSS/brand but not RAN.

MVNO margin depends on wholesale rates | We offer a full-MVNO wholesale model | MVNO launched eSIM-only activation

Network Slicing

Creating isolated, end-to-end virtual networks over shared infrastructure with tailored performance/policy for use cases.

We demoed a URLLC slice for industrial control | Slicing APIs enable enterprise self-serve QoS | SLAs map to slice templates

New Radio (NR)

The 5G air interface standard supporting flexible numerology, wide bandwidths, and advanced features like mini-slots and beamforming.

NR in n78 carries most 5G traffic | We refarmed LTE to NR in selected cells | NR-SA enabled VoNR

Non-Standalone (NSA) / Standalone (SA)

5G deployment modes: NSA anchors NR to LTE/EPC; SA uses NR with the 5G Core, enabling features like slicing and VoNR.

We launched NSA for rapid coverage | SA roll-out unlocked network slicing | VoNR requires SA plus IMS readiness

O-RAN (Open RAN)

An open, disaggregated RAN architecture with standardized interfaces and a RAN Intelligent Controller (RIC) for automation via xApps/rApps.

We trialed O-RAN vendors for DU/RU split | RIC apps optimize handovers in real time | Open fronthaul enabled multi-vendor sites

Operations Support Systems (OSS)

Systems for network planning, inventory, provisioning, fault/performance management, and service assurance.

OSS alarms flagged a fiber cut | Auto-provisioning reduced site turn-up time | Inventory accuracy in OSS improved repairs

Over-the-Air (OTA)

Remote distribution of software, configurations, and SIM profiles to devices and network elements.

We pushed an OTA radio patch overnight | eSIM profiles download OTA during activation | CPE firmware is managed OTA

Packet Core (5G Core)

The 5G core network functions (e.g., AMF, SMF, UPF, PCF) that manage sessions, policy, mobility, and user-plane forwarding.

New SMF rules enable QoS tiers | Edge UPFs localize traffic for low latency | We containerized 5GC to speed releases

Quality of Service (QoS)

Traffic handling policies that prioritize or rate-limit flows to meet performance targets such as latency or throughput.

Premium plans get higher QoS GBR | QoS maps are enforced in both RAN and core | SLA violations show up as QoS drops

Radio Access Network (RAN)

The radio part of the network—antennas, radios, and baseband—that connects user devices to the core.

RAN upgrades delivered 30% more capacity | We densified the RAN with small cells | Energy savings come from RAN sleep modes

Roaming

Service that lets subscribers use other operators’ networks domestically or internationally under wholesale agreements.

Inbound roaming minutes recovered post-travel | We negotiated lower wholesale roaming rates | Roaming steering favored partner A

SIM (Subscriber Identity Module)

A secure element (physical SIM or eSIM) that stores credentials (IMSI, keys) used to authenticate to the network.

SIM swap fraud triggered new controls | We ship IoT devices with locked SIM profiles | eSIM reduces logistics cost vs plastic SIMs

Small Cells

Low-power radio nodes that complement macro sites to improve capacity and indoor/outdoor coverage in dense areas.

We deployed small cells on street furniture | Neutral-host small cells serve multiple MNOs | Small cells offload stadium traffic

Spectrum Auction

Regulator-run process to assign licensed spectrum to operators, often with coverage obligations and caps.

Winning C-band licenses reshaped mid-band strategy | Auction prices lifted our capex guidance | Spectrum caps limited our bids

Subscriber Acquisition Cost (SAC)

All-in cost to add a new customer, including marketing, commissions, device subsidies, and onboarding.

SAC rose with flagship device promos | Lower SAC on digital-only channels | We compare SAC to CLV to set budgets

Service Level Agreement (SLA)

A contractual commitment to specific service metrics (uptime, latency, mean time to repair), often with penalties.

Enterprise slices come with strict SLAs | We report monthly SLA compliance | SLA credits applied after an outage

Total Cost of Ownership (TCO)

The full lifecycle cost to build, operate, maintain, and retire network assets, including energy and site leases.

Open RAN reduced RAN TCO by 20% | Virtualization shifted TCO from capex to opex | Tower lease escalators drive TCO pressure

TowerCo (Tower Company)

A company that owns and leases passive infrastructure (towers, rooftops) to MNOs under long-term contracts.

We sold towers to a TowerCo and leased them back | TowerCo tenancy ratios improved economics | New builds follow TowerCo MLAs

Traffic Shaping

Network techniques that manage or prioritize traffic flows to optimize performance and fairness; regulated by net neutrality rules in some markets.

We shape heavy video during peak hour | Policy shifts best-effort data to lower priority | Traffic shaping reduced congestion complaints

Uplink

The device-to-network transmission direction; typically power-limited, affecting coverage and cell-edge performance.

Uplink is the limiting factor for FWA | We added UL CA for better video calls | High-band uplink relies on sub-6GHz anchor

Unlicensed Spectrum

Spectrum open for public use (e.g., 2.4/5/6 GHz), often used for Wi‑Fi and cellular offload or LAA/NRA-U.

We offload data to Wi‑Fi in malls | 6 GHz Wi‑Fi eased indoor capacity | LAA boosted downlink in dense areas

User Plane Function (UPF)

The 5G Core function that forwards user traffic and enforces policies; can be deployed at the edge for low latency.

Local breakout via edge UPFs | Scaling UPFs handled the FWA surge | UPF selection steers traffic by slice

Voice over LTE (VoLTE)

Packet-switched voice carried over LTE via IMS; enables HD voice, simultaneous voice and data, and sunset of 2G/3G.

VoLTE penetration reached 95% of traffic | CSFB retired after VoLTE expansion | VoLTE roaming launched with partner X

Voice over NR (VoNR)

Native 5G voice over SA networks using IMS; improves call setup and can enable lower latency.

VoNR went live in SA markets | Devices fell back to VoLTE where VoNR wasn’t available | IMS tuning shortened VoNR call setup

Wholesale

B2B arrangements where MNOs sell network capacity or services (e.g., to MVNOs, IoT providers) under wholesale rates.

MVNO wholesale grew double digits | We offer wholesale 5G access with slicing options | IoT wholesale deals use private APNs