This document provides key terminologies and concepts related to the telecommunications sector. It is intended as a reference guide for professionals working in the telecommunications industry or anyone interested in understanding the technical and operational elements that support mobile communications.
A Mobile Network Operator (MNO) is a company that provides wireless communication services to users. It owns or controls the infrastructure (e.g., cell towers) and offers services like voice calls, SMS, and mobile internet.
Examples:
A prepaid card used to top up mobile account balances for services such as calls, data, and text messages. Common in prepaid mobile plans.
A digital code used to pay for services like airtime or data. Delivered via SMS, USSD, or apps. Replaces physical scratch cards.
A digital payment card issued by a mobile operator for postpaid users. Charges are added to the monthly phone bill.
A unique phone number assigned to a mobile subscriber.
Example: +93-70-123-****
Non-core telecom services like mobile internet, entertainment (TV, games), financial services, and custom features like voicemail or ringback tones. These services enhance the basic offering and provide additional revenue for telecom operators.
Summary: Non-core services like internet, games, financial services, voicemail, ringback tones.
A short code is a 3-6 digit number used for SMS/MMS services by businesses and organizations. It is commonly used for marketing, authentication (OTP), alerts, and customer support.
Short codes can be dedicated, shared, vanity, or random and are widely used for promotions, notifications, and emergency services.
Summary: A 3–6 digit number for SMS/MMS services, used for OTPs, alerts, marketing, support.
Communication between users on the same network.
Example: MTN user to MTN user call. Often cheaper or free.
Communication between different networks.
Example: Roshan user to MTN user call in Afghanistan. Usually incurs higher charges.
Number normalization is the process of converting phone numbers into a standard, consistent format so that they can be processed correctly by telecom systems, regardless of how they were originally entered or dialed.
Example:
00937012***** → Normalized:
+937012*****
07012***** → Normalized:
+937012*****
CRBT is a telecom service that lets users set a custom tone (like a song or message) that callers hear while waiting for the call to be answered.
Key Points:
Summary: Custom tone (song/message) heard by caller while waiting. Can be activated via USSD, IVR, app, or SMS.
EVD is a system for digitally selling mobile airtime, data, and services without physical scratch cards. Retailers use a digital platform (like a POS, app, or web portal) to top up customer accounts in real time. It reduces costs, improves security, and enables real-time tracking of sales and inventory.
Summary: Digital platform for topping up mobile balances. Replaces scratch cards. Enables real-time recharge, security, and tracking.
Refers to the value of a prepaid recharge or service bundle. It represents fixed amounts like 50, 100, or 500 AFN used for mobile top-ups, data, SMS, or voice packs. Denominations are commonly used in scratch cards, digital recharges, and mobile apps.
Summary: Fixed recharge values like 50, 100, or 500 AFN used for mobile top-ups.
A CDR logs voice call or SMS details such as caller, receiver, duration, time, and call status. CDR is used for: Billing, call tracking, and analytics.
Rated CDR is a type of Call Detail Record (CDR) that has been processed by a rating engine and contains the charges calculated for a specific communication event. Rated CDR contains billing information such as call costs, rates, taxes, and is used for billing and financial purposes.
An XDR records data and multimedia usage (e.g., internet, video streaming), offering more detail than a CDR. XDR is used for billing complex services and data analytics.
An EDR logs any network events, such as logins, SMS, handovers, or policy changes. EDR is used for: Network monitoring, security, and service assurance.
2G was the first digital generation of mobile networks, replacing analog systems. It introduced GSM, enabled encrypted voice calls, and brought text messaging to users. It also improved call quality, used radio spectrum (the range of frequencies used for wireless communication) more efficiently, and laid the foundation for 3G, 4G, and 5G Networks.
GPRS, also called 2.5G, is a mobile data standard built on 2G networks. It enabled packet-based data transfers at speeds around 56 to 114 Kbps. Operating on both 2G and 3G networks, GPRS powered early mobile internet services like:
UMTS, known as 3G, brought faster internet and improved voice quality. It enabled:
Speeds were typically up to 384 Kbps, and up to 42 Mbps with later upgrades (like HSPA+).
LTE, commonly referred to as 4G, is a wireless broadband standard based on 4th generation cellular technology. It delivers high-speed internet to smartphones, tablets, and other mobile devices.
LTE supports:
Typical speeds can reach 100+ Mbps, with some versions offering even more. LTE powers modern smartphone use including Netflix, cloud apps, social media, and more.
5G is the fifth generation of cellular networks. It offers ultra-fast speeds (up to 10 Gbps) and extremely low latency, enabling near-instant communication.
5G benefits applications that require high reliability and speed, such as:
VoIP allows voice and multimedia communication over IP networks (like the internet) instead of traditional phone lines. It is cost-effective, flexible, and supports services like voice calls, video calls, and messaging on various devices.
Examples: Skype, WhatsApp, etc.
HSPA+ is an enhanced 3G (3.5G/3.75G) mobile broadband technology that offers faster data speeds (up to 42 Mbps download, 11.5 Mbps upload) and lower latency compared to standard 3G.
HSPA+ is backward compatible with older UMTS/3G networks and was widely used before LTE/4G became common.
IMSI is a unique number stored on your SIM card that mobile networks use to identify and authenticate you.
Example IMSI: 412800734*****
The Country Code (like +93 or 0093) is used for making international phone calls to a specific country. For example, when dialing a number in Afghanistan from another country, you'd start with +93. The Mobile Country Code (MCC) is used internally by mobile networks to identify the country of a mobile subscriber. For Afghanistan, the MCC is 412. It's part of the IMSI (International Mobile Subscriber Identity) stored on the SIM card and used by the network during registration and authentication.
A two or three-digit code that uniquely identifies a mobile network operator within a specific country. It is used in combination with MCC to distinguish between different carriers operating in the same country.
Example MNCs:
Note: The same MNC can exist in different countries but with different MCCs.
A unique number assigned to each mobile subscriber by their mobile network operator. It identifies the individual user within that operator’s network. The format and length may vary between operators but typically consists of 9–10 digits.
Example MSINs:
IVR is a system that lets callers interact with automated voice menus using keypad input or speech. It’s used to route calls, provide information, or handle tasks like checking balances or recharging accounts without human agents.
Centralized location for monitoring and managing network operations.
A base station is a fixed communication location that enables wireless communication between a network and mobile devices. It sends and receives radio signals to/from mobile phones or other wireless devices. It consists of Antennas, transceivers, power supplies, and baseband units.
Examples: Cell towers in mobile phone networks (e.g., 4G, 5G).
Billing Pulse refers to a fixed time unit (e.g., 60 seconds) used to calculate charges for telecom services such as voice calls. Users are billed in increments of this unit, regardless of whether the entire duration is used.
Example: For a 60-second pulse rate, a 61-second call would be billed as 2 pulses.
Most common billing pulses durations are 1 second, 30 seconds and 60 seconds.
IMEI is a unique 15-digit number that identifies a mobile device. It is used by networks for device authentication and security. It can also help track, block, or blacklist lost or stolen phones.
IMEI numbers are stored in a database called the EIR (Equipment Identity Register)
EIR is a database in mobile networks that stores lists of mobile device IMEIs, it helps MNOs identify and control devices by classifying them into three lists:
EIR’s job is to check (using the IMEI number) that every phone call or SMS sent is from a mobile phone authorized to use a mobile network.
EIR helps prevent the use of stolen, faulty, or unauthorized devices on the network.
Mobile number portability enables mobile phone users to retain a mobile telephone number when changing the mobile network operator.
A telecom architecture enabling advanced value-added services like call forwarding, toll-free numbers, voicemail, and IVR. It supports dynamic call routing, prepaid billing, and service customization by separating service logic from core infrastructure, simplifying updates and new service deployment.
Summary: Telecom architecture enabling services like call forwarding, toll-free numbers, and IVR.
Manages delivery of data packets to/from mobile devices. Tracks location and manages mobility.
Interface between mobile network and external networks (like the internet). Manages IP allocation and data routing.
Routes user data between eNodeB and PGW. Handles mobility, QoS, and anchoring traffic in LTE.
Connects users to external networks. Manages IPs, QoS, billing. Evolves into UPF in 5G.
Interconnect DRs are records generated for calls, messages, or data sessions that occur between different operator networks. They track usage details like duration, time, type of service, and destination to facilitate billing and revenue sharing between operators.
Key Points:
Summary: Usage records for inter-operator communication. Used for billing, reconciliation, and revenue assurance.
PBX is a private telephone network used by businesses for internal and external communication. It manages call routing, voicemail, conferencing, and integrations. PBX can be traditional (landlines), IP-based (VoIP), or cloud-hosted for more flexibility.
Summary: Private telephone network within organizations. Can be landline-based, VoIP, or cloud-hosted.
BTS is a key component in 2g mobile telecom networks, responsible for handling wireless communication between mobile devices and the network.
It transmits and receives signals within a specific area (cell) and manages multiple calls or data sessions. BTS connects mobile devices to the broader telecom infrastructure, enabling communication.
Summary: Handles wireless communication between devices and the network.
Node B is the 3G counterpart of the BTS in 2G networks. It manages radio communication with mobile devices, transmitting and receiving signals within a cell.
Unlike BTS, Node B connects to an RNC (Radio Network Controller) and supports higher data rates and advanced 3G services like mobile internet and video calls.
eNodeB (Evolved Node B) is the 4G LTE equivalent of Node B (3G) and BTS (2G). eNodeB is the 4G base station that replaces both Node B and its controller (RNC), enabling high-speed LTE communication with simpler, faster architecture.
gNodeB (Next Generation Node B) is the 5G equivalent of eNodeB (4G). It manages radio communication between user devices and the 5G Core Network, supporting both high-speed data and ultra-low latency connections.
RNC manages multiple 3G Node Bs, controlling radio resources, handovers between cells, performs load balancing, and mobility. It connects Node Bs to the core network and ensures smooth communication in 3G networks.
Integrates voice, video, messaging, email, and collaboration into one platform.
CDMA is a wireless communication technology used in mobile networks. It allows multiple users to share the same frequency channel by assigning each call a unique code. This makes communication more efficient and secure compared to older technologies like GSM. CDMA was widely used in 2G and 3G networks, especially in North America and some parts of Asia, before LTE and 5G became dominant.
Summary: Wireless tech allowing multiple users on one frequency via unique codes.
GSM is a standard for mobile networks that enables voice and data communication. It uses digital cellular technology with SIM cards for authentication and operates on multiple frequency bands. GSM supports features like SMS, international roaming, and secure encryption for calls.
Summary: Mobile network standard using SIM cards, supporting SMS, roaming, and encryption.
Foreign user roaming on a local network.
Example: Vodafone (Germany) user on Airtel (India).
Local subscriber roaming on a foreign network.
Example: Airtel (India) user on Vodafone (Germany).
MSRN is a temporary telephone number assigned to a mobile station which roams into another numbering area (usually another country).
VLR is a temporary database in mobile networks that stores subscriber information when a user is roaming. It works with the MSC to track the user's location, authenticate them, and help route calls and messages. The VLR gets data from the HLR and deletes it when the user leaves the area.
MSC is a key component in 2G/3G mobile networks that manages call switching, mobility, SMS routing, and subscriber authentication. It connects mobile users to other networks (like landlines or the internet).
VOMS is a backend system used by telecom operators to create, manage, distribute, and validate prepaid recharge vouchers.
Key Points:
OCS is a real-time billing system used by telecom operators to charge customers instantly as they use services like Voice calls, Mobile data, SMS, Roaming and Value-added services.
Summary: Real-time billing system for charging services as they are used.
PCRF manages real-time policy control and charging decisions. It defines how data is prioritized, billed, and accessed based on user profiles and service types. It works closely with the PGW and subscriber database to enforce network rules. PCRF is a core component in LTE networks.
Summary: Manages real-time data usage policies and charging in LTE networks.
CRM helps operators manage customer interactions, track data, and improve services. It handles sales, marketing, support, and billing, enabling personalized offers, support tracking, and better customer satisfaction. CRM systems also integrate with billing to monitor usage and charges.
Summary: Tracks customer interactions, billing, and support. Improves retention and satisfaction.
HLR is a central database that stores subscriber info like profiles, subscriptions, and location data. It manages service access, tracks location for call routing, and supports services like call forwarding and voicemail. The HLR also handles authentication and call authorization.
Summary: Central database for subscriber info, location, and service access.
HSS is the central database in 4G and 5G networks that stores and manages user subscription data, authentication credentials, and mobility information.
It supports IP-based services and is a key component of the IMS (IP Multimedia Subsystem).
The percentage of customers who stop using the service within a given period.
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