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SMS and GSM related terms and glossary

Air Interface

The standard operating system of a wireless network. Air interface technologies include: AMPS, TDMA, CDMA and GSM.

AMPS- (Advanced Mobile Phone Service)

An analog cellular radio standard that serves as the foundation for the U.S. cellular industry. AMPS represents the first generation of wireless networks.


The traditional method of modulating radio signals. Most U.S. cellular phones use analog but are migrating to digital technologies. AM (amplitude modulation) and FM (frequency modulation) are the two most common methods of analog modulation. API- (Application Program Interface)

A language and message format used by an application program to communicate with the operating system or some other system or control program such as a database management system (DBMS) or communications protocol. APIs are implemented by writing function calls in the program, which provide the linkage to the required subroutine for execution. Thus, an API implies that a program module is available in the computer to perform the operation or that it must be linked into the existing program to perform the tasks. ASP- (Application Service Provider)

An organization that hosts software applications on its own servers within its own facilities. Customers access the application via private lines or the Internet. ASP is also called a "commercial service provider."

CDMA- (Code Division Multiple Access)

An air interface technology that was developed by the U.S. military and commercialized by the U.S. company Qualcomm. CDMA supports SMS with a message length of 120 characters. With CDMA, each conversation is digitized and then tagged with a code. The mobile phone receives a signal to locate that particular code and it then deciphers the conversation off the airwaves. It codes each conversation expanding it 128 times, making it easy to decipher at the receiving end. CDMA2000

3G CDMA evolution from cdmaONE supported by cdmaONE operators. Phase 1 provides 144 Kbps data rate and Phase 2 up to 2 Mbps. See Third Generation. CDMAONE

The name used by the CDMA Development Group (CDG) for CDMA networks (IS-95) using 2nd-generation digital technology. CDPD- (Cellular Digital Packet Data)

An enhanced packet overlay on analog cell phone networks used to transmit and receive data. This technology allows data files to be broken into a number of packets and sent along idle channels of existing cellular voice networks. CDPD provides 19.2 Kbps and is deployed by AT&T among several other carriers. Coverage

Refers to the region within which a paging receiver can reliably receive the transmission of the paging signals.


A digital signal is composed of electrical pulses representing either zero or one. Because digital signals are made up only of binary streams, less information is needed to transmit a message. Digital encoding therefore increases the capacity of a given radio frequency. Furthermore, only digitized information can be transported through a noisy channel without degradation. Even if corruption occurs, as long as the one zero pattern is recognizable, the original information content can be perfectly replicated at the receiving end.

GPRS- (General Packet Radio Service)

Allows information to be sent and received across a mobile telephone network that makes Internet connections easier. GPRS is used to boost wireless data transmission over GSM networks. GPRS can achieve 171.2 kilobits per second (kbps), which is about three times as fast as the data transmission speeds possible over today's fixed telecommunications networks and ten times as fast as current GSM networks. Unlike existing digital wireless Net connections, no dial-up modem is necessary.

GSM- (Global System for Mobile Communications)

A digital mobile phone standard used extensively in Europe, the Middle East, Africa, Asia and in parts of America and Canada. First introduced in 1991, the GSM standard has been deployed at three different frequency bands: 900 MHz, 1800 MHz and 1900 MHz. GSM 1900 is primarily deployed in North America. Named after its frequency band around 900 MHz, GSM-900 has provided the basis for several other networks using GSM technology. GSM uses narrowband TDMA which allows eight simultaneous calls on the same radio frequency. Along with CDMA and TDMA it represents the second generation of wireless networks.

HDML- (Handheld Device Markup Language)

A specialized version of HTML designed to enable wireless pagers, cell phones and other handheld devices to obtain information from Web pages. HDML was developed by (formerly Unwired Planet) before the WAP specification was standardized. It is a subset of WAP with some features, not included in WAP. AT&T Wireless launched the first HDML-based service in 1996.


NTT DoCoMo's mobile Internet access, launched in February 1999. I-mode is an alternative to WAP, though it is only implemented in Japan. It offers Internet access and email service. While WAP uses HDML, I-mode relies on Compact HTML (C-HTML). Both languages are a simple version of HTML, for use on mobile phones. Today more than 7000 sites are I-mode compatible and offer a wide range of services over mobile phones: mobile banking, ticket reservation, cartoons downloading, etc. IDEN- (Integrated Digital Enhanced Network)

A wireless communications technology from Motorola that provides support for voice, data, short messages (SMS) and dispatch radio (two-way radio) in one phone. Operating in the 800MHz and 1.5GHz bands and based on TDMA, iDEN uses Motorola's VSELP (Vector Sum Excited Linear Predictors) vocoder for voice compression and QAM modulation to deliver 64 Kbps over a 25KHz channel. Each 25KHz channel can be divided six times to transmit any mix of voice, data, dispatch or text message. Used by various carriers around the globe, Nextel Communications provides nationwide coverage in the U.S.

Messaging Gateway

A computer system that converts one messaging protocol to another. It provides an interface between two store and forward nodes, or message transfer agents (MTAs). Metadata

Data that describes other data. The term refers to any file or database that holds information about another database's structure, attributes, processing or changes. Metadata surrounding the Simplewire service and wireless device data includes whether a mobile device is turned on or off, the geographic location, routing commands, screen size, the amount of characters a particular phone can receive, character support, two-way capabilities and any other phone features.

One-Way Text-Messaging

Sending short (wireless data) messages to a smart phone, pager, wireless PDA or other handheld device via the Internet. Text-messaging implies sending short messages generally no more than a couple of hundred characters in length. In Europe, text-messaging was popularized by the GSM cell phone system's Short Messaging Service (SMS), which supports messages of up to 160 characters.

PCS- (Personal Communication Services)

A second-generation digital voice, messaging and data cell phone system in the 2GHz range. PCS is supported mostly by GSM.

PDC- (Personal Digital Communications)

A Japanese digital cellular standard that supports SMS.

SIM Card

Smart card that gives GSM phones their user identity. SIM cards make it easy for phones to be rented or borrowed. Smart Phone

A digital cellular phone that has text-messaging, web access and other data services along with voice. SMS- (Short Message Service)

The transmission of short text-messages to and from a mobile phone, fax machine and/or IP address. Messages must be no longer than 160 alphanumeric characters and contain no images or graphics. Once a message is sent, it is received by a Short Message Service Center (SMSC), which must then get it to the appropriate mobile device. To do this, the SMSC sends a SMS Request to the home location register (HLR) to find the roaming customer. Once the HLR receives the request, it will respond to the SMSC with the subscriber's metadata: 1) inactive or active 2) where subscriber is roaming. If the response is 'inactive' then the SMSC will hold onto the message for a period of time. When the subscriber accesses the device the HLR sends a SMS notification to the SMSC, and the SMSC will attempt delivery. The SMSC transfers the message in a Short Message Delivery Point-to- Point format to the serving system. The system pages the device, and if it responds, the message gets delivered and receives verification. SMSC- (Short Message Service Center)

The hardware device submitting the messages. Currently, SMSC devices support binary formats. A software module called the SMS gateway is used to give instructions to the SMSC. The protocol described in this draft is proposed to provide a standard for service providers to interact with SMS gateways or SMS centers. SNPP- (Simple Network Paging Protocol)

A sequence of commands and replies where pages are delivered to individual paging terminals. The most obvious benefit is the elimination of the need for modems and phone lines to produce alphanumeric pages, and the ease of delivery of pages to terminals in other cities or countries.

TAP- (Telocator Alphanumeric Protocol)

An SMS standard. The pre-cursor to TDP, a simple protocol dedicated to the forwarding of alphanumeric pages. Although the features and capabilities of TAP are in TDP, the TAP protocol may co-exist with TDP. The TAP protocol may be utilized to forward binary data to RF linked computers if input is formatted and processed. TDMA- (Time Division Multiple Access)

A method of digital wireless communications transmission allowing a large number of users to access a single radio-frequency channel without interference. Each user is given a unique time slot within each channel. SMS Mobile Originate has now gone live on several TDMA networks around the world including Telecom New Zealand, Midwest Wireless USA, Algar Telecom Brazil and Cellcom Israel. Other TDMA network operators such as AT&T Wireless in the U.S. have launched SMS MO nationally. TDP/TME- (Telocator Data Protocol)

A suite of protocols used for sending messages from a computer, through a paging system, to a mobile receiving computer. Together, these protocols define the flow of messages from input devices through several processing steps until the entire message is received by an RF linked computer. The set is compromised of several protocols including TME, TRT and TMC. Text-Messaging

See One-Way Text-Messaging and Two-Way Text-Messaging Third-Generation - (3G)

A new wireless standard promising increased capacity and high-speed data applications up to two megabits. Implemented in Europe as UMTS and cdma2000 in North America. Goals are high-quality multimedia and advanced global roaming (in house, cellular, satellite, etc.). TNPP- (Telocator Network Paging Protocol)

A one-way paging networking standard. TNPP is supported by most one-way and two-way messaging networks, but can only be used for one-way messaging. The TNPP protocol is used for moving pages from one paging system to another over standard lines. Two-Way Text-Messaging

Sending short (wireless data) messages to a smart phone, pager, PDA or other handheld device from another web enabled device. Two-way implies that the device receiving the message is able to reply via text-messaging as well. Text-messaging implies sending short messages generally no more than a couple of hundred characters in length. In Europe, text-messaging was popularized by the GSM cell phone system's Short Messaging Service (SMS), which supports messages of up to 160 characters.

VPN- (Virtual Private Network)

Private networks that are configured within a public network. Carriers build VPNs that appear as private national or international networks to the customer, but physically share backbone trunks with other customers. VPNs enjoy the security of a private network via access control and encryption, while taking advantage of the economies of scale and built-in management facilities of large public networks. VPNs have been built over X.25, Switched 56, frame relay and ATM technologies. The VPN adds an extra layer of security. A huge growth in VPN use is expected.

WAE- (Wireless Application Environment)

The part of the WAP protocol that application and service developers use most in their work. The WAE consists of the WML and WMLScript specs as well as the Wireless Telephony Application Interface (WTAI) that specifies how WAP applications can access mobile phone functionality (initiate a call, send an SMS). WAP Alert

An exclusive Simplewire product that enables wireless devices to receive a reroute via text-message to a url where the user can access more information than can be provided within the character limit of a text-message.

WAP Stack

A set of protocols that covers the whole process of wireless content delivery: From the definition of WML and WML Script for creating the actual layout of the content to the specifications of security measures in the WTLS, and to the lowest parts of the stack dealing with the actual transport of content.

WAP- (Wireless Application Protocol)

An open standard for communication between handsets and the Internet. WAP is a wireless communications environment for delivering Web data to wireless terminals with minimal screen display. An initiative started by Unwired Planet, Motorola, Nokia and Ericsson to develop a standard for wireless content delivery on the next generation of mobile communicators. WAP strips all but graphics for display on small screens, such as mobile phones. A mini-browser is an integral part of WAP enabled phones. WAP enabled phones first appeared in Europe at the end of 1999.

WCTP- (Wireless Communication Transfer Protocol)

A protocol that transfers content between wireline and wireless devices. The protocol may operate over any desired transport protocol that is block oriented. The protocol itself deliberately does not address the issues of security or authentication of transactions in a highly secure manner.

WIM- (Wireless Instant Messaging)

Bridges the gap between wired and wireless networks. WIM seamlessly allows a desktop user to instantly send a message to a handset.

WIN - (Wireless Intelligent Network)

Transaction processing infrastructure for wireless systems.

Wireless Bridge

A device used to transmit and receive radio frequencies over the air between two LANs.

Wireless LAN

A local area network that uses radio frequency transmission over the air. Works like a cellular phone system with roaming between cells.

Wireless Modem

Modem and antenna for analog and digital cellphones, CDPD, ARDIS, BellSouth Intelligent Wireless Network, etc.

Wireless Portal

A Web site that supports users with smart phones or alphanumeric pagers.

WMF- (Wireless Message Format)

A standard format for presenting data received through a paging system to mobile computers. The application at the MED uses this format to encode binary data and control information sent to a remote device. This information is received completely intact by the MCD.

WML/WMLScript- (Wireless Markup Language/Script)

The languages used to create WAP pages. WML is similar to the way HTML is used to create web pages and WMLScript is based on JavaScript. Both are adapted and optimized for a wireless environment (compression to save bandwidth).

WMP- (Wireless Message Protocol) Server

Simplewire's very own WMP server allows the Wireless Message Gateway to accept all requests regardless of carrier, intelligently translate the information into the correct wireless protocol and route the information to the correct wireless carrier. Simplewire's WMP server is able to provide subscribers with a consistent and simple interface via the Internet to any wireless device. The WMP Server is Simplewire's core technology and includes four layers of the text-messaging network. They are the Acceptance and Delivery Layer, the Processing Layer, the Consolidation Layer and the Carrier Routing Layer.

WSP- (Wireless Service Provider)

Any organization that delivers wireless services to its customers.

WTLS- (Wireless Transport Layer Security)

The security layer of the WAP which provides privacy, data integrity and authentication for WAP services. WTLS, designed specifically for the wireless environment, is needed for the client and server to be authenticated in order for wireless transactions to remain secure and also because the connection needs to be encrypted. For example, a user making a transaction with a bank over a wireless device needs to know that the connection is secure and private and not subject to a security breach during transfer. WTLS is needed because mobile networks do not provide complete end-to-end security.