Telco Term Glossary

3G - Third Generation

3GPP - 3rd Generation Partnership Project

AAL - ATM Adaptation Layer

ACD - Automatic Call Distributor

Device being used mainly in call center environments to route incoming calls to call center agents. ACDs usually support different call distribution policies.

ACFC - Address and Control Field Compression

ACK - Acknowledgment

ACM - Address Complete Message

ISUP message being sent in reply to IAM

ACR - Apply Charging

CAP Operation

ADPCM - Adaptive Delta Puls Code Modulation

A DPCM variant using different quantization steps

ADSL - Asymmetrical Digital Subscriber Line

ADSL is a specific version of DSL. In difference to DSL the data transmission rate is greater in one direction than the other.

AGCOM - Autorità per le garanzie nelle comunicazioni

Italian regulations authority for telecommunications

ALF - Application Layer Framing

APN - Access Point Name

ARCEP - Autoritè de Règulation des Communications Electroniques et des Postes

French regulations authority for telecommunications

ARPU - Average Revenue Per User

ASCII - American Standard Code for Information Interchange

ASN.1 - Abstract Syntax Notation 1

ASN.1 is a notation commonly used in telecommunications to specify protocols.

ATA - Analog Telephone Adaptor

A device frequently used with VoIP. It enables the use of VoIP with anlog telephones.

ATM - Asynchronous Transfer Mode

ATM is a data switching technology on link layer allowing for real time data (e.g. voice) and other data (e.g. IP) at carrier grade quality level on permanent and/or switched circuits (PVC/SVC). Instead of switching packets at flexible sizes up to 1500 bytes (as with Ethernet) ATM uses cell switching. ATM cells consist of 53 octets carrying 48 octets payload.

AuC - Authentication Center

A component of a GSM core service platform being connected to or part of the HLR. The AuC is an important element of the GSM network security infrastructure

BAIC - Barring of all incoming calls (Call barring services)

BAOC - Barring of outgoing calls (Call barring services)

BCSM - Basic Call State Model

Term being used in combination with IN protocols, such as CAMEL or INAP. The BCSM describes the call handling on the IN controlled switch.

BGP - Border Gateway Protocol, Routing Protocol

BICRoam - Barring of all incoming calls except home country (Call Barring services)

Sometimes also referred as BIRO

BIRO - Barring of mobile terminated calls when romaing in VPLMN country

BOIC - Barring of international calls (Call barring services)

BOICexHC - Barring of international calls except home country (Call barring services)

Sometimes also referred as BOIH

BORO - Barring of mobile originated calls when romaing VPLMN country

BPEL - Business Process Execution Language

BPO - Business Process Operator

bps - Bits per Second

BRI - Basic Rate Interface

BS - Base Station

Base stations are part of GSM radio networks. They are managed by base station controllers and interface with mobile stations (mobile phones).

BSC - Base Station Controller

Part of GSM radio network. A base station controller manages several base stations and is connected to a MSC

BSS - Base Station Subsystem (GSM)

Radio network part of GSM network comprising mobile stations (mobile phones) base stations, and base station controllers

BSS - Business Support Systems

CAMEL - Customized Applications for Mobile Enhanced Logic

An standard IN protocol mainly being used to provide prepaid subscribers with roaming functionalities without running into financial risks. Other important applications include national roaming and IN based MVNOs.

CAP - Camel Application Part, a protocol used in CAMEL servers

CAP is a protocol for call control in mobile networks (HPLMN, and VPLMN) with varying functionalities depending on CAP phase. Most commonly used for call control of pre-paid subscriptions. CAP calls are controlled by a SCP (IN).

CAPI - Common ISDN Application Programming Interface

The CAPI interface is supported by the majority of ISDN controllers.

CB - Call Barring

CBC - Cypher Block Chaining Mode

CC - Contributing Source Count

A protocol element of RTP

CC - Country Code

Part of the MSISDN E.164 structure

CCITT - Comite Consultatif International Telephonique et Telegraphique, ancestor of ITU

One of the most important standardization organizations in telecommunications

CCS - Common Channel Signalling

CD - Call Deflection

Supplementary GSM Service according to GSM 02.72

CdPN - Called Party Number

The telephone number of the called party. Frequently also referred as B-number.

CDR - Call Detail Record

The term CDR is being used for the charged activity of any particular subscriber.

CFB - Call forwarding on mobile subscriber busy

CFNA - call forwarding no answer

CFNRc - Call Forwarding on subscriber not reachable (immediate forwarding/diverting)

CFNRy - Call Forwarding on subscriber does not reply (delayed forwarding/diverting)

CFU - Call Forwarding unconditional

CgPN - Calling Party Number

The telephone number of the calling party. Frequently also referred as A-number.

CHAP - Challenge Handshake Authentication Protocol

CLI - Command Line Interface

CLIP - Calling Line Identification Presentation (Number Presentation Services)

CLIP supplementary service provides the called party with the possibility to receive the line identity of the calling party

CLIR - Caller Line ID Restriction

Blocking the transmission of the caller's telephone number

CLIR - Calling Line Identification Restriction (Number Presentation Services)

CLIR supplementary service enables the calling party to prevent presentation of its line identity to the called party

CMT - Comision del Mercado de las Telecomunicaciones

Spanish regulations authority for telecommunications

CNAME - Canonical Name

CNAP - Calling Name Presentation

Supplementary Service according to GSM 02.96

COLP - Connected Line Identification Presentation

Connected Line Identification Presentation (COLP) supplementary service provides the calling party with the possibility to receive the line identity of the connected party. COLP is a number presentation service.

COLR - Connected Line Identification Restriction

COLR supplementary service enables the connected party to prevent presentation of its line identity to the calling party. COLR is a number presentation servie.

CORBA - Common Object Request Broker Architecture

CSD - Circuit Switched Data

A term referring to GSM data services, especially for B16.

CSI - CAMEL Subscription Information

CSRC - Contributing Source Identifiers

A protocol element of RTP

CSS - Cascading Style Sheets

Cascading Style Sheets (CSS) is a style sheet language used for describing the presentation semantics (the look and formatting) of a document.

CW - Call Waiting

Call Waiting Service permits a mobile subscriber to be notified of an incoming call (as per basic call procedures) whilst the traffic channel is not available for the incoming call and the mobile subscriber is engaged in an active or held call. Subsequently, the subscriber can accept, reject, or ignore the incoming call.

DCE - Data Communications Equipment

DCS1800 - Digital Communications System 1800 MHz

DEA - Diameter Edge Agent

DECT - Digital Enhanced Cordless Telecommunications

A standard for digital cordless phones, used for domestic or corporate purposes. DECT can also be used to transfer data at limited transfer rates.

DES - Data Encription Standard

DHCP - Dynamic Host Configuration Protocol

DIAMETER - An AAA protocol, predecessor of RADIUS

DLPI - Data Link Provider Interface

DMZ - Demilitarized zone

DNS - Domain Name System

DOM - Document Object Model

DOM is a cross-platform and language-independent model for representing and interacting with HTML, XHTML and XML contents.

DP - Detection Point

Detection Point (DP) is a generic term that identifies the insertion point for IN processing in IN controlled telecommunications. A DP is either a Trigger Detection Point (TDP) or an Event Detection Point (EDP).

DRA - Diameter Routing Agent

DSL - Digital Subscriber Line

DSL allows for transmission of data over a standard telephone line (ISDN or POTS). While the standard telephony services are using the lower part of the band the data transmission takes place on higher frequencies. DSL and ADSL - a variant of DSL - are important Internet access technologies, especially for residential users.

DSLAM - Digital Subscriber Line Access Multiplexer

A device on the network side of a DSL enabled local loop with the purpose to modulate the data part of the data on the local loop. Counterpart are DSL splitter and DSL modem at the premises of the subscriber

DSS1 - Digital Subscriber Signalling 1

DTE - Data Terminal Equipment

DTMF - Dial Tone Multi-Frequency

DVI - Digital Video Interface, Intel Real-Time Video

DVMRP - Distance Vector Multicast Routing Protocol

E1 - European Digital Signal Level 1 (2 Mbps)

E3 - European Digital Signal Level 3 (34 Mbps)

EAI - Enterprise Application Integration

ECT - Explicit Call Transfer

GSM supplementary service according to GSM 02.91, Supplementary Service Group Call Offering

EDGE - Enhanced Data rates for GSM Evolution

EDP - Event Detection Point

EIR - Equipment Identity Register

The EIR is a database that contains a list of all valid mobile equipment on the network. Each MS is identified by its IMEI. An IMEI is marked as invalid if it has been reported stolen or is not type approved.

ENUM - Telephone Number Mapping

ERD - Enitity Relationship Diagram

eTOM - enhanced Telecom Operations Map

ETSI - European Telecommunications Standards Institute

EVN - Einzelverbindungsnachweis, German term for itemized (telephone) bill

FAC - Final Assembly Code

Part of the IMEI.

FDN - Fixed Dialing Numbers

This term describes a feature of GSM allowing to restrict outgoing calls to certain MSISDNs

FIFO - First In First Out

FMC - Fixed Mobile Convergence

A telecommunications terms describing products and services bridging the the gap between fixed (line) telecommunication services and mobile telecommunication services.

FNR - Flexible Numbering Register

FTP - File Transfer Protocol

GGSN - GPRS Gateway Support Node

The GGSN is the network central unit to service mobile stations via SGSNs.

GIA - General Interconnection Agreement

GMSC - Gateway MSC

GPRS - General Packet Radio Service

GPS - Global Positioning System

GRX - GPRS Roaming Exchange

GSM - Global System for Mobile Communications

GSM - Group Speciale Mobile

GSM-R - Global System for Mobile Communications - Railway

gsmSCF - GSM Service Control Function

gsmSRF - GSM Specialized Resource Function

gsmSSF - GSM Service Switching Function

GT - Global Title

GTP - GPRS Tunneling Protocol

GTT - Global Title Translation

GW - Gateway

GWT - Google Web Toolkit

Google Web Toolkit (GWT) is a development toolkit for browser-based applications.

H.323 - ITU-T Recommendation H.323

Recommendation from the ITU Telecommunication Standardization Sector (ITU-T) that defines protocols for provide audio-visual communication sessions on any packet network

HDLC - High-Level Data Link Control

HDSL - High bitrate Digital Subscriber Line

HLR - Home Location Register

The HLR can be regarded as a large database containing information on mobile subscriptions.

HOLD - Call Hold

Call hold service allows a served mobile subscriber, who is provisioned with this Supplementary Service, to interrupt communication on an existing active call and then subsequently, if desired, re-establish communication. The traffic channel remains assigned to the mobile subscriber after the communication is interrupted to allow the origination or possible termination of other calls

HPLMN - Home PLMN

HSCSD - High Speed Circuit Switched Data

HSDPA - High-Speed Downlink Packet Access

HSS - Home Subscriber Server

HSUPA - High Speed Uplink Packet Access

HTTP - Hypertext Transfer Protocol

IAM - Initial Address Message

The ISUP initial address message (IAM) is sent by the originating switch to reserve resources for a call. It is the first step of setting up the call.

ICCID - Integrated Circuit Card ID

Serial number of a SIM card.

ICMP - Internet Control Message Protocol

IEEE - Institute of Electrical and Electronics Engineers

IETF - Internet Engineering Task Force

IGMP - Internet Group Management Protocol

IGP - Interior Gateway Protocol, Routing Protocol

ILP - Integrated Layer Processing

IMAP - Internet Message Access Protocol

IMEI - International Mobile Equipment Identity

Identifies the Mobile Station. Can be retrieved on most mobile terminals by pressing '*#06#'. Conists of TAC, FAC and SNR.

IMPS - Instant Messaging and Presence Service

IMS - IP Multimedia Subsystem

IMSI - International Mobile Subscriber Identity

IN - Intelligent Network

INAP - Intelligent Network Application Part

IP - Internet Protocol

IP - Intelligent Peripheral

IPCP - PPP Internet Protocol Control Protocol

IPLMN - Interrogating PLMN

IPSec - IP security

A number of IP protocols for secure communications ofver the Internet

IPv4 - Internet Protocol Version 4

IPv4 is the Internet Protocol Version being used commonly today.

IPv6 - Internet Protocol Version 6

IPv6 is the next generation Internet Protocol. It introduces new adressing schemes and longer adresses and solves many issues of IPv4.

IPX - Internetwork Packet Exchange Protocol

ISC - International Switching Centre

The ISC serves as gateway between a national network and the international network. It is part of the international interconnection infrastructure of an operator.

ISDN - Integrated Services Digital Network

ISP - Internet Service Provider (Internet Context), Independent Service Provider (GSM Context)

ISUP - ISDN User Part

ISDN User Part (ISUP) is used in telecommunications to setup and release voice channels.

ITIL - IT Infrastructure Library

ITP - IP Transfer Point

A network device usually translating between SS7 over TDM and SIGTRAN

ITU - International Telecommunication Union

IVR - Interacitve Voice Responder

kbps - KiloBits per Second

L2TP - Layer Two Tunneling Protocol

LAN - Local Area Network

LBS - Location Based Services

LCP - Link Control Protocol

LDAP - Lightweight Directory Access Protocol

LLC - Logical Link Control

LPC - Linear Predictive Codec

LTE - Long Term Evolution

LTE, marketed as 4G LTE, is a standard for high-speed data communications on cellular networks for mobile phones and data terminals.

M2PA - MTP Level 2 Peer Adaptation

M2UA - MTP Level 2 User Adaptation

M3UA - MTP Level 3 User Adaptation Layer

MAN - Metropolitan Area Network

A network (with usually high data transmission rates) spanning the geoprahical area of a city.

MAP - Mobile Application Part

The MAP is an extension to the Ss7/C7 protocols providing support for cellular networks (GSM).

MBONE - Multicast Backbone

MCA - Missed Call Alert

The missed call alert service informs subscribers unreachable usually via SMS on missed calls

MCC - Mobile Country Code

MCU - Multipoint Control Unit

MGW - Media Gateway

MGw - Media Gateway

MIB - Management Information Base

An SNMP term describing the monitoring capabilities of a network device.

MIME - Multipurpose Internet Mail Extensions

MIME is an Internet standard allowing E-Mails to carry attachments and rich formatted contents. MIME also plays an important role in MMS.

ML - Move Leg

CAP (CAMEL) Operation

MM1 - MMS protocol being used between mobile terminal and MMSC

MM3 - MMS protocol being used between external servers like e-mail server and MMSC

MM4 - MMS protocol being used for MMSC interconnection

MM7 - MMS protocol being used by large accounts (contents provider) to access MMSC

MMS - Multimedia Messaging Service

MMSC - Multimedia Messaging Service Center

MMSI - Maritime Mobile Service Identity

MNC - Mobile Network Code

MNO - Mobile Network Operator

Mobile Network Operators are running a GSM/UMTS network consiting of BSS (base station subsystem, radio network), NSS (network and switching subsystems) and OSS (operation and maintenance centers). MNOs in Germany are T-Mobile, Vodafone, E-Plus and O2.

MNP - Mobile Number Portability

Mobile Number Portability allows mobile subscribers to take the existing MSISDN withe them, even if they change the the MNO. From the MNO/MVNO perspective it is a thread to allow subscribers to take their MSISDN with them. However, regulations in Europe vary and MNP is partly successful.

MO - Mobile Originated

MOC - Mobile Originated Call

A call originated by a mobile subscriber. The so called A-leg of the call is mobile originated and needs to be managed by the mobile network operator (MNO) serving the customer.

MPTY - Multi Party Service (GSM service for multipoint calls)

MS - Mobile Station

MSB - Most Significant Bit

MSC - Mobile service Switching Centre

The MSC provides switching services to the network and serves a number of BSCs. It provides routing of incoming and outgoing calls. It also provides mobility functions like registration, authentication, location update, MSC handovers and call routing to roaming subscribers.

MSC-S - MSC Server

MSIN - Mobile Station Identification Number

MSISDN - Mobile Subscriber ISDN Number, Mobile Station International Subscriber Directory Number, Mobile Station ISDN Number

The telephone number of a mobile subscriber.

MSN - Multiple Subscrib. Number

MSRN - Mobile Station Roaming Number

MSS - Mobile Soft Switch

Similar to MSC

MSS - MSC Server

MT - Mobile Terminal

Another term for mobile station (MS) or handset.

MT - Mobile Terminated

MTA - Message Transfer Agent

MTC - Mobile Terminated Call

MTP - Message Transfer Part

MTTD - Mean Time To Detection

MTU - Maximum Transmission Unit

MVNE - Mobile Virtual Netwok Enabler

The MVNE is a technical service provider enabling MVNOs to offer mobile telecommunication services to the public. A MVNE has usually no contractual relationship with the end customer nor does he own a MVNO contract with a MNO host.

MVNO - Mobile Virtual Network Operator

MVNOs are using the Base Station System (radio network) of other Mobile Network Operators (MNOs) to offer Mobile Telephony Services. There are two major MVNO models in Europe: With the MVNO light model the MVNO receives call control via IN/CAP services. The call model is more or less like national roaming. The MVNO does not operate an HLR and he is not required to operate even a switch. With the full MVNO model, the MVNO operates the full core network infrastructure including HLR and switches. Examples for MVNOs in Europe are Virgin in UK (running on the T-Mobile network) in UK and Simyo running on the Orange network) in Spain.

NCP - Network-Layer Control Protocol

NDC - National Destination Code

Part of the MSISDN E.164 structure

NI - Network Indicator

Network Indicator is a subfield in the Signaling Information Octet (SIO). It permits discrimination between national and international messages, when NI is: 0=international, 1=reserved, 2=national, and 3=national spare.

NIC - Network Information Center

NISDN - Narrowband ISDN

NP - Numbering Plan

NPDB - Number Poratbility Database

An acronym frequently used in the context of (mobile) number portability. A NPDB is used for routing an charging.

NRN - Network Routing Number

NSDU - Network Service Data Unit

NSP - Network Services Part

NSS - Network and Swirching Subsystems (GSM)

Service delivery platform and switching part of GSM network comprising at least switches (MSC), home location register (HLR), Authentication center (AuC), and VLR. EIR is also part of NSS.

NTP - Network Time Protocol

Internet application protocol for synchronization of computer clocks.

NUP - National User Part (SS7)

O&M - Operations and Maintenance

O-BSCM - Origintating Basic Call State Model

O-CSI - Originating CAMEL Subscription Information

OCCF - Operator Controlled Call Forwarding

OCS - Online Charging System

An Online-Charging-System provides session based charging functions and event based charging functions from a various number of sources. See 3GPP TS 32.296 for overview.

ODBC - Open Database Connectivity

OFCS - Offline Charging System

OMA - Open Mobile Alliance

OMC - Operations and Maintenance Center

ORLCF - Optimal Routing at Late Call Forwarding

OSA - Open Service Access

OSI - Open Systems Interconnection

OSPF - Open Shortest Path First, Routing Protocol

OSS - Operator Specific Service

OSS - Operations Support Subsystem (GSM)

OTA - Over The Air

OTAP - Over The Air Provisioning

OVIS - HP OpenView Internet Services (tm)

An End-to-End Service Management tool being part of the Hewlett Packard OpenView Suite

PAP - Password Authentication Protocol

PBX - Private Branch eXchange

PC - Point Code

A Point Code in SS7/C7 is like an IP address on the Internet. Each active signaling component has a point code. There are national and international point codes. Each STP, SCP, and SSP has at least one point code associated.

PCEF - Policy and Charging Enforcement Function

PCH - Packet Charger

Charging device in the IP payload traffic path for packet switched data (GPRS/UMTS)

PCM - Puls Code Modulation

PCRF - Policy and Charging Rules Function

PCU - Packet Control Unit

PDH - Plesiochronous Digital Hierarchy

PDP - Packet Data Protocol

Packet Data Protocol (PDP) context allows the MS to exchange data packets.

PDU - Protocol Data Unit

PFC - Protocol Field Compression

PIC - Point in Call

PIM - Protocol Independent Multicast

A family of multicast routing protocols that can provide one-to-many and many-to-many distribution of data over the Internet

PIM - Personal Information Management

PIN - Personal Identification Number

PLMN - Publc Land Mobile Network

POI - Point of Interconnection

POP - Post Office Protocol

PoP - Point of Presence

POTS - Plain Old Telephone System

PPP - Point-to-Point Protocol

PPP - Point to Point Protocol

PPPoE - Point-to-Point Protocol over Ethernet

PPTP - Point-to-point tunneling protocol

PRI - Primary Rate Interface

PSP - Payment Service Provider

PSTN - Public Switched Telephone Network

PUK - Personal Unblocking Key

PVC - Permanent Virtual Circuit

PVN - Private Virtual Network

QoS - Quality of Service

RADIUS - Remote Authentication Dial In User Service

RAN - Radio Access Network

RARP - Reverse Address Resolution Protocol

RED - Random Early Detection

RF - Radio Frequency

RFC - Request for Comments

RI - Routing Indicator

SCCP protocol field

RIP - Routing Information Protocol

RSVP - Resource Reservation Protocol

RTCP - RTP Control Protocol

RTCP - Real-Time Transport Control Protocol

RTP - Real-time Transport Protocol

RTT - Round Trip Time

SAP - Service Access Point

SAP - Session Announcement Protocol

SAP - SIM Access Profile

SAT - SIM Application Toolkit

SAT allows for customized applications residing on the SIM of a MS. The MS is being used as terminal for the interaction with the subscriber. Frequently used to enable voice and data VAS. SAT applications also play an important role for dual- or multiple IMSI solutions.

SBC - Session Border Controller

SC - Service Center (for SMS)

SCCP - Signaling Connection Control Part

SCF - Service Control Function

Functional entity of SCP facilitating the execution of IN services

SCP - Service Control Point

SDH - Synchronous Digital Hierarchy

Synchronous Optical Networking (SONET) and Synchronous Digital Hierarchy (SDH) are standardized protocols that transfer multiple digital bit streams over different medias.

SDP - Session Description Protocol

SDR - Service Detail Record

SEI - Software Engineering Institute

SGSN - Serving GPRS Support Node

SGSN delivers data from and to mobile stations within the network area and provides mobility management, link management and authentication.

SIGTRAN - Signaling Transport

SIGTRAN is the acronym for SS7 over IP. The majority of MNOs is currently subsituting their traditional network infrastructure towards new standards. SIGTRAN introduction is an important element of this.

SIM - Subscriber Identity Module

SIP - Session Initiation Protocol

A frequently used protocol for VoIP signalling and VoIP session management. While H.323 still dominates the business segment, SIP is the de-facto standard for VoIP signalling in the resdiential customer segment.

SLA - Service Level Agreement

SLIP - Serial Line Internet Protocol

SLO - Service Level Objective

SM - Short Message

SMB - Server Message Block Protocol

SMF - Service Management Function

SMPP - Short message peer-to-peer protocol

A protocol frequently being used for large accounts to access SMSCs

SMS - Short Message Service

SMSC - Short Message Service Center

SMTP - Simple Mail Transfer Protocol

SN - Subscriber Number

Part of the MSISDN E.164 structure. Identifies a subscriber in a network or numbering area.

SNMP - Simple Network Management Protocol

SNR - Serial Number

Part of the IMEI.

SOA - Service-Oriented Architecture

SOAP - Simple Object Access Protocol

SOAP is a protocol for remote procedure calls using the web. It provides web services. SOAP interfaces are specified using WSDL (Web Services Description Language)- a XML language deploying XSD.

SONET - Synchronous Optical Network

SP - Service Provider

SPX - Sequenced Packet Exchange

SRF - Signalling Relay Function

There may be different types of SRFs in a mobile network. One of the more important ones is the MNP-SRF (Signalling Relay Function for support of MNP).

SRI - Send Routing Information (MAP)

SS-CSI - Supplementary Service Notification CAMEL Subscription Information

SS7 - Common Channel Signaling System No. 7

SSF - Service Switching Function

Unit of switch/MSC handling IN protocol

SSL - Secure Socket Layer

SSP - Service Switching Point

Typically a voice switch or MSC

SSRC - Synchronisation Source Identifier

A protocol element of RTP

STK - SIM ToolKit

STP - Signal Transfer Point

Transfer Point for SS7 messages between networks, like a router in IP networks

STUN - Simple Traversal of UDP (User Datagram Protocol) through NATs (Network Address Translators)

SVC - Switched Virtual Circuit

T-BCSM - Terminating Basic Call State Model

T-CSI - Terminating CAMEL Subscription Information

TAC - Type Approval Code

Part of the IMEI.

TACACS - Terminal Access Controller Access Control System

TAP - Transferred Account Procedure

Transferred Account Procedure is being used by mobile operators to exchange roaming billing information

TCAP - Transaction Capabilities Application Part

TCP - Transmission Control Protocol

TDD - Time Division Duplex

TDM - Time Division Multiplexing

TDSV - Telekommunikations-Datenschutzverordnung

German telecommunications data security regulation act, latest version from 2000, depreciated by TKG 2004

TKG - Telekommunikationsgesetz

German Telcommunications Act, current version: June, 11th 2004

TKUeV - Telekommunikations-Ueberwachungsverordnung

TLNV - TeilnehmerverhŠltnis

TOS - Type-Of-Service (IP)

TR - Technical Reference

TTL - Time To Live

TUP - Telephony User Part

UDP - User Datagram Protocol

An IP based transport protocol for datagrams. Being used for many higher level protocols. It does not provide reliable delivery. RTP is based on UDP.

UE - User Equipment

UMA - Unlicensed Mobile Access

Allows seamless handover between licensed telecommunication networks (GSM, GPRS, EDGE, UMTS) and unlicensed telecommunication networks (e.g. WLAN, Bluetooth)

UML - Unified Modeling Language

UMTS - Universal Mobile Telecommunications System

UNI - User to Network Interface

URL - Uniform Resource Locator

USIM - Universal Subscriber Identity Module

USSD - Unstructured Supplementary Service Data

UTRAN - Universal Terrestrial Radio Access Network

VADSL - Very high bitrate Asymmetrical Digital Subscriber Line

VC - Virtual Circuit

VDSL - Very-high-bit-rate Digital Subscriber Line

VHDSL - Very High bitrate Digital Subscriber Line

VLAN - Virtual Local Area Network

VLR - Visitor Location Register

VMS - Voice Mailbox System

VMSC - Visited Mobile Switching Centre

The MSC (Mobile Switching Centre)serving a mobil subscriber in the VPLMN (Visited Public Land Mobile Network)is named VMSC.

VoD - Video on Demand

VoIP - Voice over IP

VPLMN - Visited PLMN

Visited Public Land Mobile Network

VPN - Virtual Private Network

VRF - Virtual Routing and Forwarding

WAN - Wide Area Network

WAP - Wireless Application Protocol

WFQ - Weighted Fair Queuing

WiFi - Wireless Fidelity (WLAN)

Another term for WLAN

WIN - Wireless Intelligent Network

WLAN - Wireless LAN

WML - Wireless Markup Language

WPAN - Wireless Private Area Network (IEEE 802.15.4) also called ZigBee protocol

A Small range wireless network (240Kbps --- 30 meters) when compared with Bluetooth(IEEE 802.15.1 --- 1Mbps --- 10 meters)

WSP - Wireless Session Protocol

WWW - World Wide Web

X.25 - ITU protocol for packet switched WAN networks

XML - Extensible Markup Language

XSD - XML Schema Definition

XSL - Extensible Stylesheet Language

XSL-FO - Extensible Stylesheet Language – Formatting Objects

XSLT - XSL Transformation

YUI - Yahoo User Interface Library

YUI is a JavaScript and CSS library with more than 30 unique components including low-level DOM utilities and high-level user-interface widgets.