Sierra Corporate Glossary

2130891 Rev 3

Preface

Important Due to the nature of wireless communications, transmission and reception of data Notice can never be guaranteed. Data may be delayed, corrupted (i.e., have errors) or be totally lost. Although significant delays or losses of data are rare when wireless devices such as the Sierra Wireless are used in a normal manner with a well-constructed network, the Sierra Wireless modem should not be used in situations where failure to transmit or receive data could result in damage of any kind to the user or any other party, including but not limited to personal injury, death, or loss of property. Sierra Wireless accepts no responsibility for damages of any kind resulting from delays or errors in data transmitted or received using the Sierra Wireless modem, or for failure of the Sierra Wireless modem to transmit or receive such data.

Safety and Do not operate the Sierra Wireless modem in areas where blasting is in progress, Hazards where explosive atmospheres may be present, near medical equipment, near life support equipment, or any equipment which may be susceptible to any form of interference. In such areas, the Sierra Wireless modem MUST BE POWERED OFF. The Sierra Wireless modem can transmit signals that could interfere with this equipment. Do not operate the Sierra Wireless modem in any aircraft, whether the aircraft is on the ground or in flight. In aircraft, the Sierra Wireless modem MUST BE POWERED OFF. When operating, the Sierra Wireless modem can transmit signals that could interfere with various onboard systems.

Note: Some airlines may permit the use of cellular phones while the aircraft is on the ground and the door is open. Sierra Wireless may be used at this time.

The driver or operator of any vehicle should not operate the Sierra Wireless modem while in control of a vehicle. Doing so will detract from the driver or operator's control and operation of that vehicle. In some states and provinces, operating such communications devices while in control of a vehicle is an offence.

Limitation of The information in this manual is subject to change without notice and does not Liability represent a commitment on the part of Sierra Wireless. SIERRA WIRELESS AND ITS AFFILIATES SPECIFICALLY DISCLAIM LIABILITY FOR ANY AND ALL DIRECT, INDIRECT, SPECIAL, GENERAL, INCIDENTAL, CONSEQUENTIAL, PUNITIVE OR EXEMPLARY DAMAGES INCLUDING, BUT NOT LIMITED TO, LOSS OF PROFITS OR REVENUE OR ANTICIPATED PROFITS OR REVENUE ARISING OUT OF THE USE OR INABILITY TO USE ANY SIERRA WIRELESS PRODUCT, EVEN IF SIERRA WIRELESS AND/OR ITS AFFILIATES HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES OR THEY ARE FORESEEABLE OR FOR CLAIMS BY ANY THIRD PARTY. Notwithstanding the foregoing, in no event shall Sierra Wireless and/or its affiliates aggregate liability arising under or in connection with the Sierra Wireless product, regardless of the number of events, occurrences, or claims giving rise to liability, be in excess of the price paid by the purchaser for the Sierra Wireless product.

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Patents This product may contain technology developed by or for Sierra Wireless Inc. This product includes technology licensed from QUALCOMM® . This product is manufactured or sold by Sierra Wireless Inc. or its affiliates under one or more patents licensed from InterDigital Group.

Copyright © 2011 Sierra Wireless. All rights reserved.

Trademarks AirCard® and Watcher® are registered trademarks of Sierra Wireless. Sierra Wireless , AirPrime, AirLink, AirVantage and the Sierra Wireless logo are trademarks of Sierra Wireless. Windows® and Windows Vista® are registered trademarks of Microsoft Corporation. Macintosh® and Mac OS® are registered trademarks of Apple Inc., registered in the U.S. and other countries. QUALCOMM® is a registered trademark of QUALCOMM Incorporated. Used under license. Other trademarks are the property of their respective owners.

Contact Information Sales Desk: Phone: 1-604-232-1488 Hours: 8:00 AM to 5:00 PM Pacific Time E-mail: [email protected] Post: Sierra Wireless 13811 Wireless Way Richmond, BC V6V 3A4 : 1-604-231-1109 Web: www.sierrawireless.com

Consult our website for up-to-date product descriptions, documentation, application notes, firmware upgrades, troubleshooting tips, and press releases: www.sierrawireless.com

4 2130891 Preface

Revision History Revision Release Changes number date

1.0 July 2007 This document has received a new part number (previously 2110032).

Substantial changes have been made since the previous version to remove references to dated technology, and to incorporate new and upcoming developments.

2.0 Feb. 2010 Applied new template.

3 March 2011 Updated patent information.

Rev 3 Mar.11 5 Sierra Wireless Corporate Glossary

6 2130891 Numerics

1X First version of 3G CDMA wireless technology that permits data rates of up to 153 kbps downlink and uplink on a single CDMA channel. Also known as CDMA2000.

1xEV-DO Rev. 0 An upgrade to 1X that increases downlink speeds up to 2.4 Mbps.

1xEV-DO Rev. A An upgrade to 1xEV-DO Rev. 0 that supports IP packets, increases downlink speeds up to 3.1 Mbps, and increases uplink up to 1.8 Mbps.

3G Third Generation Wireless—The generic term for the next generation of mobile communications networks. As defined by the ITU, the major improvements over technologies such as 1X and GPRS are increased network capacity and data transfer rates. See also 1xEV-DO Rev. 0, 1xEV-DO Rev. A, EDGE, and HSPA.

3GPP Third Generation Partnership Project—A collaboration agreement that was established in 1998 by standards bodies in , , , North America, and South . 3GPP was tasked to create a globally applicable 3G system that would fit into the International Union’s International Mobile Telecommunications-2000, or IMT-2000, project. 3GPP specifications are based on evolved GSM specifications, now generally known as the UMTS system.

3GPP LTE 3GPP Long Term Evolution—A 3GPP project to improve UMTS for future requirements by improving efficiency, services, and the use of technology, as well as lowering costs. Its intent is to result in release 8 of the UMTS standard.

4G Fourth Generation—Further standards for improvements on 3G that are being developed by the ITU. Though not yet complete, one goal is data transfer speeds of 1 gigabit per second (Gbps) while stationary.

802.11 Family of wireless (wireless LAN) standards more commonly known as Wi-Fi, developed by working group 11 of the IEEE.

Numerous standards have been developed by this group, denoted by letters, beginning with “a”, after “802.11”. As of 2007, the most widely-utilized standards are 802.11b and 802.11g. In general, subsequent standards provide for faster downlink and uplink speeds, as well as greater range. For more information, consult www.ieee.org.

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A activation The process of setting up an account so that you can connect to the .

ACK A signal sent to acknowledge the reception of a packet. Contrast with NAK.

AGC Automatic Gain Control—A mechanism to automatically adjust a microphone or speaker based on input levels.

AirCard® PC Card™ made by Sierra Wireless, offering data services over the cellular phone infrastructure.

ANSI American National Standards Institute—Consult www.ansi.org.

AP Access Point—See .

API Application Program Interface—A language that enables communication between computer programs, in particular between application programs and control programs.

ASCII American (National) Standard Code for Information Interchange—An 8-bit data code used by most computers and many devices.

ASIC Application-Specific Integrated Circuit—A computer chip designed specifically for a particular circuit board or piece of electronic equipment. It is intended for sale to only one company and is typically developed to meet that company’s design objectives for a particular application. asynchronous A method of transmitting information that involves sending data one character at a time. The sending computer puts a start bit at the beginning of each character transmitted and at least one stop bit at the end. Contrast with synchronous.

AT command Attention command—A set of modem commands, preceded by “AT,” originally developed by Hayes, Inc. for their modems. The structure, but not the specific commands, which vary greatly from manufacturer to manufacturer, is a de facto modem industry standard.

ATM Asynchronous Transfer Mode—A method of broadband switching. A format, carrying voice, fax, LAN and data traffic, supporting speeds up to 2.2 GB/sec; a standard for high-speed, packet-switched networks.

B The data transmission capacity of a line or connection. The value is expressed in bits per second; its frequency range is measured in Hz.

8 2130891 The range of frequencies, expressed in bits per second, that can pass over a given data transmission channel within a network. The amount of bandwidth determines the rate at which information can be sent through a channel. The greater the bandwidth, the more information that can be sent in a given amount of time.

base station A station in the Domestic Public Cellular Radio Telecommunications Service that provides the means for mobile stations (for example, phones and radio modems) to access network services using radio.

A cell, a sector within a cell, a Mobile Switching Center (MSC), an Interworking Function (IWF), or another part of the cellular system located at a cellular radio tower.

baud A measure of the number of signal-state changes per second; for example, voltage or frequency changes. It is sometimes, but not always, the same as the number of bits per second.

BLER BLock Error Rate—A measure of the percentage of data blocks that could not be fully corrected by the Forward Error Correction (FEC) scheme.

BoD Bandwidth on Demand—A temporary increase to the data capacity of a wired or wireless link to accommodate increased traffic.

bps bits per second—The actual data speed over the transmission medium. See also baud.

broadcast A UDP function that supports the sending of data with a single transmission to all the registered IP addresses in a given area. See also multicast.

BS/MSC The base station (BS) and the Mobile Switching Center (MSC) functioning as a single entity in the sending and receiving of data.

buffer An area in a device used to temporarily store data.

byte An 8-bit data symbol that has 256 possible combinations. Bytes are usually represented by two hexadecimal (0-F) digits. If the symbol can be displayed, printed, or is used for control purposes, it can also be referred to as a character, for example, ASCII. Not all bytes are characters by this definition.

C

Caller ID A feature that sends the names and phone numbers of callers between the first two rings.

carrier The frequency that is modulated by the data.

CCITT Consultative Committee on International and Telephony—A United Nations organization that establishes electronic communications standards.

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CCT CDMA Configuration Tool—a Sierra Wireless product used to configure Sierra Wireless modems.

CDMA Code Division Multiple Access—A wideband technique used in digital cellular, personal communications services, and other wireless networks. Wide channels (1.25 MHz) are obtained through spread spectrum transmissions, thus allowing many active users to share the same channel. Each user is assigned a unique digital code, which differentiates the individual conversations on the same channel. See also TDMA.

CDMA2000 See 1X.

CDMAOne The IS-95 CDMA standard developed by QUALCOMM Inc. cell The RF area controlled by one cellsite. Cells are usually hexagonal and can be anywhere from 0.4 to 15 miles in radius.

CGSA Cellular Geographic Service Area—The physical area over which a cellular carrier is licensed to provide service. character Any symbol that can be displayed as text on the screen, printed, or used for control purposes. Generally it is represented by an 8-bit element of data. checksum A way of detecting data transmission errors by finding the sum of the data as represented by numbers.

CINR Carrier to Interference-plus-Noise Ratio—Strength of the carrier signal compared to the interferer (interference + noise). client A computer originating a data conversation (to request service from a server).

CLNS Connectionless Network Service—A service that routes each packet individually within the network based on the destination address carried in the packet and knowledge of the current . Also referred to as a datagram service.

CnS Control and Status—Sierra Wireless initialism for language that allows a modem to communicate with a host. It contains a set of objects and parameters that allow an application to query the modem for status, set parameters and configuration of the modem, and receive event notifications.

COM The serial communications port of a computer. command The exchange of data in AT commands between the host (DTE) and modem (DCE). command buffer Distinct from the data receive and transmit buffers, it retains the contents of the last issued command until the AT prefix is received for the next command. This allows the repeating of the last issued command by entering A/ instead of AT.

10 2130891 compression A technique used to reduce the number of bits that have to pass over the link in order to get a message from one end to the other. The modem converts a stream of data bits from the host into a shorter stream of bits by applying special compression algorithms.

CONNECT A message indicating that the modem has made the transition from command state to data state. In other words, commands have been exchanged with the modem and data is being sent through it.

connection • A physical link between two pieces of hardware. • A logical link that connects the modem to the network. CRC Cyclical Redundancy Check—An error detection scheme in which a block check character is generated for a block of transmitted data and sent across the link. The CRC is recalculated at the receiving end and then compared with the received CRC; if they do not match, the received block is not acknowledged.

CSC Circuit Switched Cellular—V.xx modem communications over a . It uses a dedicated connection circuit, in contrast to packet-switched. The user is charged by the carrier for the duration of the connection.

CSD —A way to transmit data over older CDMA (IS-95) networks when 3G is unavailable.

CTS Clear To Send—An RS-232 control signal used in hardware flow control, issued in response to RTS.

D

data Information exchanged between a source and destination. This can consist of a single bit or a long string of bits, depending on the application.

data block A unit of data sent by the mobile/base station that transports user data and signaling traffic.

data communication The modem protocol layer that is closest to the hardware and deals with the modulation scheme used to transmit and receive the raw data that is presented to the layer above. It is concerned mainly with establishing the modulation scheme that will give the highest throughput (bps) on a given physical point-to-point connection.

datagram A packet that may or may not contain other packets and is transmitted via the Protocol.

DB-9 A 9-pin serial connector type commonly found on communications cables and used by computers and modems.

DB-25 A 25-pin serial connector type commonly found on communications cables and used by computers and modems.

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dBm A logarithmic (base 10) measure of relative power (dB for decibels); relative to one milliwatt (m). A dBm value will be 30 units (1000 times) larger (less negative) than a dBW value because of the difference in scale (milliwatts vs. watts). dBW A logarithmic (base 10) measure of power (dB for decibels); relative to one watt.

DCD Data Carrier Detect—An RS-232 status signal usually used to indicate the presence of the carrier frequency.

DCE Data Communication Equipment—When the modem is connected to a computer running a terminal emulation program, the computer and terminal emulation program perform the role of the DTE, while the modem fills the role of the DCE.

DHCP Dynamic Host Configuration Protocol—A protocol used to automatically assign IP addresses and related information. DHCP also provides safe, reliable TCP/IP network configuration.

DL Downlink (Rx) —network to modem.

DLL Dynamic Link Library—a module that contains functions and data. A DLL is loaded at run time by its calling modules (.exe or .dll). When a DLL is loaded, it is mapped into the address space of the calling process.

DNS Domain Name Server—Internet server that supplies the mapping of domain names to IP addresses. dormant A data link layer state the modem switches to from the active state after a certain period of inactivity. This reduces unnecessary network traffic. download The receiving of information through a modem from the host server to the client. Contrast with upload.

DSCP Differentiated Service Code Point—A six-bit field in an IP packet that assigns a pre-determined level of service to the packet. See also QoS.

DSR Data Set Ready—An RS-232 control signal used to signal the attached host device (DTE) that the modem (DCE) is powered on and ready to communicate.

DTE Data Terminal Equipment—The device that generates or is the final destination of data. When the modem is connected to a computer running a terminal emulation program, the computer and terminal emulation program perform the role of the DTE while the modem fills the role of the DCE.

DTMF Dual Tone MultiFrequency—A combination of two tones produced from a 2D matrix on a modem or touchtone phone.

DTR Data Terminal Ready—A RS-232 control signal used to signal the modem (DCE) that the attached host device (DTE) is powered on and ready to communicate.

12 2130891 DUN Dial-Up Networking—a Windows® protocol for connecting a computer to a server via a telephone.

DVB-H Digital Video Broadcasting-Handheld—Part of the set of DVB standards which allows mobile operators to multicast signals to mobile handsets. DVB-H technology adapts the DVB system for transmission of digital television to handheld, battery-powered receivers. Consult www.dvb-h.org.

E

E911 Enhanced 911—The capability to automatically identify, to emergency dispatchers, the location from where a wireless call is being made.

EAP Extensible Authentication Protocol—An authentication framework most commonly used in wireless local area networks. By itself it is not an authentication method; instead it defines message formats for authentication methods that are based on it.

ECCT Enhanced Computer Controlled Teletext Circuits—A GUI-based Windows program from Sierra Wireless that uses CCT to configure the modems. ECCT is more suitable for configuring a small number of modems.

Ec/Io Energy per chip/Total Noise Density—a measurement of the pilot channel's signal strength as a function of the total interference density in the CDMA carrier band.

ECM Error Correction Mode—A mode of operation for T.30 fax service that reliably provides end-to-end data transport.

EDGE Enhanced Data Rates for Global Evolution—A third-generation packet network that supports data rates of up to 384 kbps. The capacity of cellular networks is increased by allowing callers to share a channel. Each channel, divided into time slots, can be used for six transmissions. See also Evolved EDGE.

EEPROM Electronically Erasable Programmable Read Only Memory—A memory chip that can be recorded or erased by an electric signal while attached to the circuit board, but does not lose its content when electrical power is removed. Firmware is stored in EEPROMs. See also RAM and flash memory.

EFS Embedded File System—A file system embedded within a device where non- volatile memory (NVM) is typically used for storage.

EIA Electronic Industries Alliance—An alliance of electronics manufacturing trade associations, including the TIA. The EIA helps ANSI develop standards for electronics, telecommunications, and Internet security.

EONS Enhanced Operator Name String—A feature that allows the operator to define the operator name displayed for any registered network based on the MCC, MNC, and LAC which the MS is currently registered on.

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ERI Enhanced Indicator—An indicator on a mobile phone that lets you know which partner network you’re currently roaming on. This is in contrast to a roaming icon which tells you that you’re on a partner network, but not which one. error control The modem protocol layer that implements one of a number of error encoding and detection schemes on outgoing and incoming data frames respectively. This layer also takes care of the retransmission of corrupted packets to ensure that data delivered to the layer above it is error free. error detection A protocol that allows the modem to detect errors in a transmission. If an error is found the receiving modem requests the sending modem to re-transmit the data.

ESD Electrostatic Discharge—The sudden and momentary electric current that flows between two objects at different electrical potentials (such as ground). The term is usually used in the electronics and other industries to describe momentary unwanted currents that may cause damage to electronic equipment.

ESN Electronic Serial Number—The unique serial number assigned to the modem for circuit switched cellular use. See also MEID.

Ethernet The most widely-used networking technology for LANs. See LAN and RJ-45.

Evolved EDGE Further improvements to EDGE that aim to improve data transfer rates as well as increase network capacity.

ExpressCard™ Add-in memory and communications cards for portable computers that come in two form factors, ExpressCard/34mm and ExpressCard/54mm. ExpressCard is a trademark of the PCMCIA.

F facsimile (fax) The process by which a document is scanned, converted into electrical signals, transmitted, and recorded or displayed as a copy of the original.

FCC Federal Communications Commission—The U.S. federal agency that is responsible for interstate and foreign communications. The FCC regulates commercial and private management, sets rates for communications services, determines standards for equipment, and controls broadcast licensing. Consult www.fcc.gov.

FDD Frequency Division Duplex—Method of separating downlink and uplink transmissions into sub-bands so they will not interfere with each other.

FEC Forward Error Correction—Used by the MAC layer protocol to correct for airlink data errors. Implementation uses a Reed-Soloman algorithm that divides the 378- bit airlink data into 63, 6-bit symbols and can correct a block with errors in up to seven symbols.

FER Frame Error Rate—The probability that a given portion of frames will contain errors.

14 2130891 Firmware Software stored in read-only memory (ROM) or EEPROM, essential programs that remain even when the system is turned off. Firmware is easier to change than hardware but more permanent than software stored on disk.

flash memory A small, printed circuit board that stores large amounts of data (for example, network addresses and other user data) in non-volatile memory.

FLO™ Forward Link Only—Technology developed by QUALCOMM that supports the delivery of multimedia services such as television to mobile users. Data transmission is one-way, from broadcast tower to the user’s device. See also MediaFLO™.

flow control Also known as handshaking, a standard for controlling the flow of data, in either direction, between a modem and an attached device to prevent overruns. Implementation can be by hardware (RTS/CTS) or software (X-ON/X-OFF).

Forward Fundamental A Fundamental Code Channel that operates in the forward direction, from base Code Channel stations to mobile.

Forward A Supplemental Code Channel that operates in the forward direction, from base Supplemental Code stations to mobile. Channel

Forward Traffic One Forward Fundamental Code Channel and optionally up to seven Forward Channel Supplemental Code Channels used to transport data blocks from the base station to the MS. See also Reverse Traffic Channel.

frame A block of data formed from binary codes to be sent with a header and error detection information over a communications channel.

frame relay A high-speed, packet-switching technology that transmits data between intelligent end-points like routers or Frame Relay Access Devices (FRAD) at speeds between 56 kbps and 1.544 Mbps. Data is divided into variable-length frames by the sending device; each frame contains a header with address information. The frames are transmitted intermittently over digital circuits and reassembled at the receiving end.

FTP File Transfer Protocol—A TCP/IP based protocol for transferring files.

full duplex Simultaneous two-way independent transmission of data in both directions across the link. This type of connection exists in both the wireless PSTN and wireless cellular links. While the user is sending data to another computer, that computer can be simultaneously sending data back to the user.

Fundamental Code A portion of a Forward Traffic Channel or Reverse Traffic Channel that is always Channel present. It carries primary and secondary traffic, signaling, and power control information.

fundamental data A data block, potentially containing primary, secondary and/or signaling traffic, block transmitted on the Fundamental Code Channel by the base/mobile station.

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Fundamental RLP An RLP frame carried in a fundamental data block. Frame G gateway A device that connects two or more incompatible network protocols.

GB/sec Gigabytes per second—1 billion (109) bytes per second, usually used in reference to data transfer rates.

GPRS General Packet Radio Services—A 2.5-generation technology that can offer wireless data access speeds of up to 144 kbps in end-user devices.

GPS Global Positioning System—A system that uses a series of 24 geosynchronous satellites to provide navigational data.

GSM Global System for Mobile Communications—An international standard for cellular networks; used mainly in Europe and . Consult www.gsmworld.com.

GUI Graphical User Interface — A visual representation of the available functions in a program. These functions are usually accessed by using a pointing device such as a mouse to select various icons, menus, and text. A well-know GUI is Windows.

H half duplex A link where transmission occurs in either direction, but not at the same time. While the user is sending data to another computer, that computer cannot send data back to the user. handoff The process of changing radio channels in a cellular system. The user device switches from one radio frequency in the old cell to a new radio frequency in the new cell. handshaking The process in which a modem negotiates or exchanges basic information with another modem to determine which protocols will be used for connectivity.

HARQ Hybrid Automatic Repeat Request—An error control method that speeds up the recovery of corrupted packets by storing them at the receiving end. These are then combined with retransmitted packets to increase the probability of creating a good packet. HARQ is used in HSDPA and HSUPA.

HDML Handheld Device Markup Language—A derivative of Hypertext Markup Language (HTML) for handheld wireless devices. header Control information that ensures the datagram is sent to the correct address. host • A computer that uses a modem or a similar device to answer a calling computer. • A source or destination in the communication network.

16 2130891 • A computer that contains data or files to be accessed by client computers. Also known as a server. hotspot A wireless LAN that provides Internet connection and VPN access from a given location.

A Wi-Fi hotspot can be broadcasting or non-broadcasting. Broadcasting Wi-Fi hotspots transmit their SSID, allowing any Wi-Fi network adapter within coverage to detect them. Non-broadcasting hotspots do not transmit their SSIDs.

HSDPA High Speed Downlink Packet Access—An enhancement to WCDMA networks that provides higher downlink data speeds for applications such as video downloads and large file transfers.

HSPA —A family of protocols that improve upon the performance of the UMTS protocol. See HSDPA and HSUPA.

HSPA+ HSPA Evolution—A protocol defined in 3GPP release 7, proposing 42 Mbps downlink and 11 Mbps uplink.

HSUPA High Speed Uplink Packet Access—An enhancement to WCDMA networks that provides higher uplink data speeds for applications such as VPN access and large file transfers.

HTTP Hypertext Transfer Protocol—The communications protocol used to connect to Web servers.

I

ICMP Internet Control Message Protocol—A protocol included in the network layer for CDMA analog fax services.

IEEE Institute of Electrical and Electronic Engineers—A standards setting organization. Consult www.ieee.org.

IMS IP Multimedia Subsystem—Framework, designed by the 3GPP, which uses IP as the basis for delivering multimedia content to both wireless and wired terminals.

IMSI International Mobile Subscriber Identity—A unique number, usually about 15 digits long, that identifies GSM and UMTS network users.

Internet address A 32-bit source or destination address that is given an IP number and is assigned to hosts using IP.

IP Internet Protocol—The basic Internet transport mechanism.

IPv4 Internet Protocol version 4—The current, 32-bit version of IP. Its purpose is to define computer addresses on the Internet. It provides for 232 (about 4.3 billion) unique addresses. However, the number of available addresses is quickly dwindling, making NAT necessary.

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IPv6 Internet Protocol version 6—The proposed, 128-bit successor to IPv4. Its main purpose is to increase the number of available addresses to 2128, so that NAT is not required.

IP address A unique address on the Internet. Each modem must have one, to operate on a packet. The IP address is a unique number consisting of four, 1- to 3-digit numbers separated by dots. See also DNS.

IPCP Internet Protocol Control Protocol—A protocol that negotiates a temporary IP address for the mobile station whenever a transport layer is actively opened. See also DHCP.

IRC Internet Relay Chat—A way for users to send text messages to one another over a network of Internet servers. Requires an IRC client program.

IrDA InfraRed Data Access—A port on many portable computers used to exchange information.

IS Interim Standard—A standard that exists after the TIA has received industry consensus. The TIA then forwards the standard to ANSI for approval.

IS-54 The first generation of the digital standard time division multiple access (TDMA) technology.

IS-95 The standard for CDMA.

ISO International Organization for Standardization—A standards setting group. Consult www.iso.org.

ISP Internet Service Provider—A company that provides network connectivity for client computers.

ITU International Telecommunication Union — A United Nations agency headquartered in Geneva, Switzerland. It develops standards encompassing various areas of telecommunications including wired and wireless, allocates radio spectrum, and organizes communications agreements between countries.

IWF Interworking Function—A function that converts information for one or more network entities. A data service IWF enables a mobile station to communicate with data terminal equipment connected to the network.

K kbps kilobits per second—1000 bits per second, not 1024. Usually used in reference to data transfer rates. See also bps.

18 2130891 L

LAC Location Area Code—A unique five-digit identifier for a mobile station (MS) within a mobile network.

LAN Local Area Network—A small that covers at most several buildings. It is characterized by wired connections that do not permit access to anyone not physically connected to the network. Contrast with WAN. See .

LCP Link Control Protocol—used in PPP.

LED Light Emitting Diode—A diode that emits visible or infrared light.

logic sleep A mode of operation that reduces power consumption when the logic functions are idle.

M

MAC Medium Access Control—A unique identifier for a network adapter such as an Ethernet card.

MAS Mobile Application Subsystem—The combination of the Sierra Wireless modem and the attached remote device (computer or user terminal device).

Mbps Megabits per second — 1 million bits per second, usually used in reference to data transfer rates.

MCC Mobile Country Code—Each mobile device on a wireless network has an MCC, which identifies it as originating from a particular country. The MCC is determined by the International Telecommunication Union (ITU).

Mcps Megachips per second—The chip (bit) rate, sometimes used in place of bps.

MDT Mobile Data Terminal—An alternate name for an MAS. See also RTU.

MediaFLO™ QUALCOMM technology that enables the broadcasting of audio and video streams to mobile 3G devices in the . See also FLO™.

MEID Mobile Equipment Identifier—The unique second-generation serial number assigned to the AirCard or ExpressCard for cellular network use. Compare to ESN.

mesh Way of connecting a network so that each node has multiple connections to other nodes. This forms a reliable network since blockages or outages in a particular node(s) can be circumvented by ‘hopping’ around the affected node(s).

MFC Microsoft Foundation Classes—An an application framework formed by the combination of the Windows API and C++ programming language classes.

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MHz Mega-Hertz—One million cycles per second.

MIB Multipurpose Interface Board—A component of the Sierra Wireless OEM Developer’s Toolkit.

MIMO Multiple Input Multiple Output—The use of multiple antennas at both the transmitting and receiving ends to improve the range and quality of a transmission.

MIN Mobile Identification Number—A number that identifies a specific mobile unit within a wireless carrier’s network.

MNC Mobile Network Code—A two-digit number used in combination with a mobile country code (MCC) to uniquely identify a mobile service provider.

MNP Microcom Networking Protocol—Ten levels (MNP-1 through MNP-10) of and error correction techniques that allow a modem to communicate at a faster than normal rate.

MOB Modem Object—A statistical object that updates in real time to reflect modem operation. Users can query a MOB to determine how the modem is working on the network. mobile (noun) See MS (mobile station). mobile IP A communications protocol that allows mobile users to move their device from one network to another while keeping the same IP address. modem A modulator/demodulator. The modem takes a digital signal from a host computer and modulates it on an analog carrier frequency. At the receiving end, the modem demodulates the analog signal, extracting the data from the carrier.

Modem Emulation A wireless data service in which the mobile terminal appears as a standard Service telephone modem to a data terminal. modem pool A wireless data service that inserts a modem tuned for cellular operation between the mobile modem and wireline modem for improved performance. modulation The process of changing the carrier’s amplitude, frequency, or phase to impose the transmission of a signal on a carrier wave.

MP modem Mobile Product modem—A Sierra Wireless ruggedized modem used for wireless data services primarily in vehicles. Includes a GPS module.

MS Mobile Station—A terminal, such as a cell phone, , or radio modem, that is considered a station in the Cellular Service.

MSC Mobile Switching Center—The MSC switches traffic originating from or terminated by mobile stations (MS). Usually connected to at least one base station, the MSC may also be connected to other public networks (PSTN, ISDN, etc.), other MSCs in the same network, or those in different networks.

20 2130891 MSE Mean Squared Error—The value returned from the AT command AT&&R4C. Supported by the MP modem family of modems, the MSE is in hexadecimal format and is a measure of noise. Thus, the higher this value, the lower the connection speed.

MSL Master Subsidy Lock—A password that allows a user to configure parameters that are normally not accessible. See also OTSL.

MTP Monitoring and Tracking Protocol—A protocol used by MP modems to report GPS data.

MTSO Mobile Telephone Switching Office—See MSC.

multicast A UDP function that supports the sending of a single data stream in a single transmission to registered IP addresses on a specific group list. See also broadcast. Contrast with unicast.

MUX multiplexer—A telecommunications device that temporarily combines two or more signals into a single signal and transmits it onto one physical channel.

N

NAK Negative Acknowledge—A transmission control character sent as a reply when the receiving end is not ready to respond, the message is not received, or an error is detected. Contrast with ACK.

NAK List A list maintained by RLP that associates a missing data’s 12-bit sequence number with the retransmitted data frame’s 8-bit sequence number.

NAM Number Assignment Module—Semi-permanent information stored in the NOVRAM, including the modem’s Mobile Identification Number, the station class mark, carrier code, and other cellular identifiers. Essentially the phone number, it should be treated as confidential information and should not be disclosed to anyone other than the cellular service provider.

NAT Network Address Translation—The process whereby service providers’ network servers assign private IP addresses to registered devices, since public IP addresses are not needed to route data within the network. (This saves a service provider the expense of having a large pool of public IP addresses.)

When data packets pass from the network into the Internet a public IP address is substituted for the private IP address. This public IP address might be used on data transmissions from many different devices. The network server is only aware of this substituted public IP address. If other servers reply to this address, the network server cannot identify the device for which the data is intended.

NDA Non-Disclosure Agreement—A contract through which two or more parties agree not to disclose information covered in the contract.

Rev 3 Mar.11 21 Sierra Wireless Corporate Glossary

NDIS Network Driver Interface Specification—A programming interface specification developed by Microsoft and 3Com for connecting network interface cards in Windows. See also RNDIS.

NEMA National Electrical Manufacturers Association—A standards setting body. Consult www.nema.org. network A group of hosts or computers linked by logical connections.

NIC Network Interface Card—A piece of hardware that allows a computer to communicate over a network. Also known as a network adaptor.

NID Network ID—Your personal, unique identifier on a computer network. The form and format differs depending on the system you are accessing.

NMEA National Marine Electronics Association—A standards-setting body that has created the standards for exchanging GPS data between navigation devices. Consult www.nmea.org.

NOVRAM Non-volatile Random Access Memory—Random Access Memory that remembers its contents even if the power is removed.

NVM Non-volatile Memory—Computer memory that can retain stored information even when not powered.

O octet A standard byte of 8 bits.

OEM Original Equipment Manufacturer—A company that manufactures a product and sells it to a reseller.

OFDM Orthogonal Frequency Division Multiplexing—A wireless modulation technique whereby a single transmitter uses multiple (sometimes thousands) of orthogonal subcarriers to send a signal that is resistant to multi-path interference.

OFDMA Orthogonal Frequency Division Multiple Access—Improvements to OFDM that permit simultaneous transmissions from multiple users. offline State of a modem when it is disconnected from any remote terminal or is without an active network session.

OK On a system with a Hayes-compatible modem, this message appearing on the console indicates that the command entered by the user was accepted and processed. online State of a modem when it is actively connected to a remote terminal or has a network session open.

22 2130891 oscillator A device for producing alternating current. Refers especially to a radio frequency or audio frequency generator.

OSI Open Systems Interconnection—An ISO model that divides the communications process into seven distinct layers, stacked one above the other, hence the term “protocol stack”.

OTA Over The Air—The act of sending signals by a wireless device through open space.

OTSL One-Time Subsidy Lock—A password that allows a user to configure parameters that are normally not accessible. The OTSL is in effect for only one session. See also MSL.

P

packet A short, fixed-length block of data, including a header, that is transmitted as a unit in a communications network.

PAD Packet Assembler/Disassembler—A hardware device that makes it possible for a data terminal not set up for to use a packet switching network. It assembles data into packets (and adds header information) for transmission, and disassembles the packets on arrival so they can be used.

PAN Personal Area Network—A network characterized by its limited range, usually a few metres. It is comprised of devices such as mobile telephones and personal digital assistants that are used for connecting to larger networks such as the Internet.

parity A simple method of detecting if the character just received over the link is what was transmitted. A single bit is added to the binary string of bits representing the character to be transmitted. This bit is set to make the total number of binary ones in the character string plus the parity bit equal to an even or an odd number. There are five types of parity: (E)ven, (O)dd, (M)ark, (S)pace, and (N)one.

PBX Private Branch Exchange—A private telephone system that provides switchboard service, phone extensions, and access to the public telephone network.

PC Card™ Add-in memory and communications cards for portable computers. PC Card is a trademark of the Memory Card International Association (PCMCIA).

PCMCIA Personal Computer Memory Card International Association—The organization that standardizes ExpressCards and PC Cards. Consult www.pcmcia.org.

PCS Personal Communications Services—A cellular communication infrastructure that uses a different frequency range than analog mobile phone systems.

Rev 3 Mar.11 23 Sierra Wireless Corporate Glossary

PDA Personal Digital Assistant—A handheld device for managing appointments, phone lists, and other personal data such as email.

PDF Portable Document Format—A method of exchanging documents with preserved formatting between different systems. Based on Postscript, it is proprietary to Adobe Systems Incorporated. phase The time displacement between two signals.

PIN Personal Identification Number—A series of numbers (usually four) used to verify authority to access or change information.

Ping A program used to test network connectivity by sending data that is then echoed by the remote station. Ping is handled in the protocol stack that is transparent to the application layer.

POP3 Post Office Protocol, Version 3—A protocol by which a client machine can retrieve mail from a mail server. See also SMTP. port • A standard piece of the TCP address structure. The port serves as an extension of the IP address to permit a single host (one IP address) to provide multiple servers (applications), each defined by its unique port number. The port number is used to direct TCP traffic to the correct appli- cation. • The socket on the computer that allows external devices such as a modem or printer to be attached. • The process of modifying software to bring it from one type of computer system to another—for example, to translate a Windows program so that is will run on an Apple computer. POS Point of Sale—Place where sales and purchases are made using terminal devices that are connected by a network.

PPP Point-to-Point Protocol—An alternative communications protocol used between computers, or between computers and routers on the Internet. PPP is an enhanced SLIP.

PRI Product Release Instructions—A file that contains the settings used to configure modems for a particular service provider, customer, or purpose.

PRL Preferred Roaming List—An account configuration item set by your service provider. It controls the radio channels used by the device. See also roaming. protocol A defined procedure for determining the proper way of exchanging information on a network.

PSTN Public-Switched Telephone Network—The public telephone system.

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QAM Quadrature Amplitude Modulation—A form of modulation that uses amplitude, frequency, and phase to transfer data on the carrier wave.

QNC Quick Net Connect—A simplified way to dial into an Internet connection using CSD, assuming CSD is supported by your service provider.

QoS Quality of Service—Control mechanisms that prioritize data flows depending on how the data will be used.

QPSK Quadrature Phase Shift Keying—Modulation used by WCDMA.

R

RAS Remote Access Services—Any combination of software and hardware that enable access to a network that resides elsewhere.

RAM Random Access Memory—The working memory of a computer in which data is temporarily stored. Data in the RAM will be lost if electrical power is removed before the data is saved to disk.

Reed-Soloman See FEC. algorithm

Reverse Fundamental A Fundamental Code Channel that operates in the reverse direction, from mobile Code Channel to base station.

Reverse A Supplemental Code Channel that operates in the reverse direction, from mobile Supplemental Code to base station. Channel

Reverse Traffic One Reverse Fundamental Code Channels and optionally up to seven Reverse Channel Supplemental Code Channels used to transport data blocks from the mobile station to the base station.

RF Radio Frequency—Range within which radio waves are transmitted, from 3 kHz to 300,000 MHz.

RFC Request for Comments—The generic name that refers to a series of specifications developed by the Internet Engineering Task Force (IETF). The specifications include surveys, measurements, proposed and accepted TCP/IP protocol standards.

RI Ring Indicator—An RS-232 control signal used to indicate an incoming call or packet.

RJ-11 Registered Jack-11—A four-conductor jack used to connect to the PSTN.

Rev 3 Mar.11 25 Sierra Wireless Corporate Glossary

RJ-45 Registered Jack-45—An eight-conductor plug or jack used most widely in Ethernet connections. See LAN.

RLP Radio Link Protocol—This protocol improves the error characteristics of the wireless link, thereby reducing the need for transport layer retransmission due to lost data.

RMA Return Material Authorization—Process where the purchaser or recipient of defective goods returns them to the manufacturer or supplier to have them repaired or replaced.

RNAP Remote Network Access Protocol—A Sierra Wireless proprietary protocol used to send data between an MP modem and a remote server.

RNDIS Remote Network Driver Interface Specification—Similar to the NDIS, which provides specifications for network interface cards (such as Ethernet cards), RNDIS provides specifications for devices that use Plug and Play technology such as USB. roaming Situation where a cellular subscriber is in an area where service is obtained from a cellular service provider that is not the subscriber’s provider.

RS-232 An EIA hardware standard. It defines the most common type of serial communications port hardware, covering signal definitions, pin assignments, voltage and impedance levels, and inter-device signaling rules.

RS-232-C The most common type of serial transmission standard. EIA RS-232-C is a set of data transfer procedures, and more importantly, a set of standards for voltages and pin usage on a serial connector.

RSSI Received Signal Strength Indication—The signal power level at the of the modem, usually measured in dBm. See also dBW.

RSVP Resource ReSerVation Protocol—An Internet control protocol that is sent by hosts as a path message in order to request a specific quality of service (QoS) for transmissions such as voice or video traffic.

RTP Real-time Transport Protocol—Application-layer protocol for delivering real- time audio and video over the Internet.

RTS Request to Send—An RS-232 control signal used in hardware flow control.

RTU Remote Terminal Unit—Another name for a MAS; usually implies a fixed location telemetry device.

RXD Received Data—One of the RS-232 data lines used to send data from the remote terminal to the host. See also TXD.

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SDK Software Developers Kit—A package of subroutines and utilities provided by a company to programmers with the intent that they will use the SDK to develop applications that will complement the company’s products.

SER Symbol Error Rate—Percentage of symbols in error. See also SIE.

serial A method of data transmission where each bit of the character is sent sequentially over a link.

server A computer answering a data request from a client.

SID System Identifier—Identifies your home network area and is used in conjunction with your phone number to determine if you are at home or roaming.

SIE Symbols in Error—Used in computing the SER.

SIM Subscriber Identity Module—The part of the modem containing the IP address and authentication credentials.

SIP Session Initiation Protocol—An application-layer protocol primarily used for voice over IP (VoIP), but which can also be used for initiating and terminating communications sessions of all kinds, such as instant messaging. Part of IMS.

SKU Stock Keeping Unit—Identifies an inventory item. A unique code consisting of letters and/or numbers, assigned to a product by a retailer for purposes of identification and inventory control.

sleep mode A mechanism that switches off some internal components to reduce power consumption. See also logic sleep.

SLIP Serial Line Internet Protocol—The original communications protocol used between computers, or between computers and routers on the Internet. This protocol allows applications, such as Watcher®, to communicate with the modem by exchanging datagrams across the serial port connection. See also PPP.

SMA SubMiniature Version A—A standard, screw-on type radio frequency 50 ohm miniature connector for .

SMB SubMiniature Version B—A standard, push-on type radio frequency 50 ohm miniature conductor for coaxial cable.

SMS Short Messaging Service—A feature that allows users of a wireless device to receive or transmit short, alphanumeric messages (up to 160 characters, depending on the service provider).

SMTP Simple Mail Transfer Protocol—A protocol used for Internet email. See also POP3.

Rev 3 Mar.11 27 Sierra Wireless Corporate Glossary

SNMP Simplified Network Management Protocol—A set of standards for communication with devices connected to a TCP/IP network. Examples of these devices include routers, hubs, and switches. SNMP permits remote monitoring and controlling of communication devices.

SNR Signal to Noise Ratio—Ratio of the strength of the signal to that of any noise, expressed in decibels. See also dBm and dBW. socket An Internet address including the IP number and especially the TCP port. speed buffering The simplest form of buffering allows for line speed differences and busy conditions between the host (DTE) and modem and between the modem and the remote terminal (DCE). To prevent buffer overflows, flow controls must be used.

S-Registers Status Registers—A set of storage locations within the modem that hold status and control information for use by the modem firmware and the user’s application. Many can be set by the user when configuring the modem, or when activating diagnostic functions. See also WS–Registers.

SSID Service Set Identifier—The name assigned to the network. Depending on how the hotspot is configured, an SSID and/or WEP key may be required to connect to the hotspot. You obtain these from the Wi-Fi network operator. stack Refers to the TCP protocol stack, so-called because it is composed of a number of protocol layers (physical, data link, network, transport, and so on). It is required to operate with IP and can be implemented in software or hardware (modem firmware). start bit The bit preceding each asynchronous character. Signals the receiving modem that a new character is starting. There is always one start bit. stop bit There is typically one stop bit at the end of each character to be transmitted. Resets the UART in preparation for receiving the next character.

Supplemental Code An optional portion of a Forward or Reverse Traffic Channel. It carries either Channel primary or secondary traffic. supplemental data A data block, potentially containing primary, secondary and/or signaling traffic, block transmitted on the Supplemental Code Channel by the base or mobile station.

Supplemental RLP An RLP frame carried in a supplemental data block. Frame

SWI Sierra Wireless, Inc. Consult www.sierrawireless.com. synchronous A method developed to transmit multiple characters (a data block) at one time. Each block of multiple 8-bit characters is preceded and followed by a synchronizing bit sequence to maintain character synchronization with the modem. See also asynchronous.

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TAIP Trimble ASCII Interface Protocol—Trimble's GPS interface protocol used with many vehicle and fleet monitoring programs. Consult www.trimble.com.

TCP Transmission Control Protocol—The common underlying used on the Internet. A connection handshake establishes a point to point logical connection. In contrast to UDP, TCP ensures both ends of the connection are present and active on the network, thereby ensuring delivery of datagrams.

TDMA Time Division Multiple Access—A mechanism to allow multiple users to share the same radio channel by allocating users specific time slots, thereby increasing the capacity of cellular networks. Contrast with CDMA.

Telnet A protocol used for remote terminal connection service. It allows users to log on to a remote host computer and operate as if they were directly connected to that host.

TIA Telecommunications Industry Association—A standards-setting trade organization, whose members provide communications and information technology products, systems, distribution services, and professional services in the United States and around the world. Consult www.tiaonline.org.

TIES Time Independent Escape Sequence—A method of shifting the modem from data state to command state while retaining the underlying remote connection.

TNC RF connector type. TNC is an industry standard type of threaded coaxial connectors used primarily for RF applications.

traffic channel A Forward or Reverse Fundamental Code Channel used to send user data and signaling traffic between the base station and the mobile station. It has up to seven optional Supplemental Code Channels.

TTY Acronym for a teletypewriter, a device that allows hearing and speech impaired people to use a telephone.

TXD Transmit data — An RS-232 signal line that transmits data from the host to the remote terminal. See also RXD.

U

UART Universal Asynchronous Receiver/Transmitter—A chip inside the computer that converts the 8-bit character representation into a serial format, and vice versa. The UART also performs the insertion and deletion of the stop bit, start bit, and parity. It can simultaneously send and receive data in a full duplex fashion.

UDK Universal Development Kit—Developed by Sierra Wireless to facilitate all phases of the hardware integration process. The Kit is a hardware development platform that is designed to support multiple members of the wireless embedded

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module product family. It contains the hardware components that are typically necessary for evaluating and developing the module. The Kit includes a development board, cables, antennas, and other accessories.

UDP User Datagram Protocol—A low-overhead, connectionless, packet delivery IP protocol. Unlike TCP, UDP does not guarantee delivery of datagrams.

UL Uplink (Tx)—Data transfer from modem to network.

UMB Ultra —Brand name for the 3GPP project to improve the 1X standard. Key improvements are scalable bandwidth, mixed cell sizes, and increased downlink and uplink speeds of 275 Mbps and 75 Mbps respectively. Slated for commercial release in mid-2009.

UMTS Universal Mobile Telecommunications System—The European implementation of the 3G wireless phone system. unicast Practice of transmitting one data stream to a single user at a time. If there are multiple users, multiple data streams are sent. Contrast with multicast upload Sending a file or program from the client to the host server via the modem. Contrast with download.

URL Universal Resource Locator—An Internet address for a web page or file. The DNS may be used to derive the Internet Protocol address of the URL.

USB Universal Serial Bus—Standard for connecting devices in serial to a computer. Most notable for supporting hot-swapping of devices, which allowed devices to be connected and disconnected from a computer without first powering it off.

USB full speed Refers to a USB data transfer rate of up to 12 Mbps, which is supported by the USB standards 1.0 and 1.1 (which is the most common standard).

USB high speed Refers to a USB data transfer rate of up to 480 Mbps, which is supported by the USB standard 2.0. However, not all devices that are advertised as being USB 2.0 compliant are capable of the maximum transfer rate. Also known as USB “Hi- Speed”.

UTC Universal Coordinated Time—UTC replaces Greenwich Mean Time as the basis for standard time throughout the world. UTC, which uses atomic measurements rather than the earth’s rotation, is the equivalent of mean solar time at the prime meridian (0° longitude).

V

VOIP Voice Over Internet Protocol—The use of the Internet as a telephone service. It requires broadband service.

VPN Virtual Private Network—Means of encrypting data that is sent by a remote user over another network such as the Internet.

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WAN —A network that uses high-speed packet switched lines to serve a large geographic area.

WAP Wireless Application Protocol—A set of protocols used to efficiently provide Internet information over wireless communication networks to microbrowser- based devices such as smart phones.

Watcher® A Sierra Wireless program that runs on the user’s computer. It allows the user to configure the Sierra Wireless modem for communications, and monitors various modem parameters. It is not compatible with other vendor’s modems.

WCDMA Wideband CDMA—Early 3G standard for cellular carriers that use TDMA or GSM technology. Used by UMTS.

WEP Wired Equivalent Privacy—Part of the 802.11 wireless networking standards, WEP is a way to control access to a hotspot. Depending on how the hotspot is configured, a WEP key and/or an SSID may be required to connect to the hotspot. You may obtain these from the Wi-Fi network operator.

Wi-Fi Wireless Fidelity—Name for the most common standard (802.11) of high- frequency wireless local area network (WLAN). See also hotspot.

Wi-MAX Worldwide Interoperability for Microwave Access—A series of standards introduced in 2001 intended to permit broadband-like speeds over longer distances than Wi-Fi permits.

Winsock The Windows Socket interface between a user application and the TCP/IP stack.

wireless A communications link that does not involve a hardwired connection. An example of a wireless link is radio.

wireline A communications link that involves a hardwired connection. For example, the public switched telephone network (PSTN).

WLAN Wireless Local Area Network—A local area network that operates over the air in unlicensed radio frequency bands. A WLAN does not require line of sight and typically has a range of several hundred feet, though this will be limited by obstructions such as buildings. See also Wi-Fi. Contrast with Wi-MAX.

WS–Registers A set of modem registers used to handle the configuration of operations specific to wireless communication. See also S-Registers.

WWAN Wireless WAN.

WWW World Wide Web — An Internet-based, hypertext, graphical network created by Tim Berners-Lee while he was working at the European Organization for Nuclear Research (CERN) in Switzerland. For more information about the continuing development of the Web, consult www.w3.org.

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X

X.25 A CCITT protocol that allows for communication between user devices in packet- switched mode and packet-switched Public Data Networks.

X-OFF Transmission (of data) Off—A message sent to the transmitting computer, informing it to stop sending data to the receiving computer that has a full buffer.

X-ON Transmission (of data) On—A message sent to the transmitting computer, indicating it may resume sending data to the receiving computer.

Z

Z-MODEM A file transfer protocol that transmits data between modems in blocks of 512 bytes. It is fast because it does not wait for positive acknowledgement (ACK) after each block of data, but will resend a block if it receives a negative acknowledgement (NAK). Z-MODEM allows the transfer to resume where it left off following a communications failure.

Z-MODEM is the recommended file transfer protocol for the modem in Circuit Switched Cellular (CSC) mode.

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