| - A - | |
| access control | A network function that determines whether a particular mobile device is permitted to access the network. |
| adaptive retransmission algorithms | Used by self-adjusting timers to determine and dynamically set timers to effectively adjust data traffic in the event the link is slower than usual due to congestion or other network conditions. |
| Advanced Mobile Phone System (AMPS) | The North American analog cellular phone system. The spectrum allocated to AMPS is shared by two cellular phone companies in each area or region (geographic market). This system was deployed during the 1980s and today it and its variants represent nearly 85% of the cellular voice systems installed throughout the world. |
| AMPS | See Advanced Mobile Phone System. |
| analog signal | A continuously variable waveform (such as a sound wave) that can represent an infinite number of values; wireline telephone systems use analog signals to provide voice communication. The term "analog" is used to refer to telephone transmission and/or switching that is not digital. Analog signals are amplified rather than regenerated. |
| ANSI | American National Standards Institute. A group that certifies organizations developing US standards for the information processing industry. ANSI accredited groups participate in defining network protocol standards. |
| API | Application Program Interface. |
| Application Layer | Layer 7 in the Open Systems Interconnect (OSI) 7-Layer Network Layer Reference Model. Provides protocols and services required by particular user-designed application processes. Functions pertaining to particular user requirements and application service elements that can be used by more than one application are contained in this layer. |
| application program interface (API) | The interface between the subscriber unit and the multiple application subsystem. Generally consists of simple commands such as "open a connection." These commands are translated by the enabling layer into commands that either control the network connection or communicate data across the network. |
| ARDIS | A wireless packet-switched network for public data communications, jointly owned by Motorola and IBM, that allows people carrying handheld devices to send and receive short data messages. |
| ARP | Address Resolution Protocol. An Internet protocol that runs on Ethernet and all IEEE 802.X Local Area Networks (LANs), and maps Internet addresses to Medium Access Control (MAC) addresses. |
| ASCII | American Standard Code for Information Interchange. |
| ASN.1 | Abstract Syntax Notation One. A specification language used to define interoperable interfaces, based on standard application layer protocols such as Message Handling System (MHS) or Common Management Information Protocol (CMIP). |
| - B - | |
| backbone | The backbone is the part of the communications network that interconnects Local Area Networks (LANs) together inside a building or across a city or country. LANs are connected to the backbone via bridges and/or routers and the backbone serves as a communications highway for LAN-to-LAN traffic. A backbone can be a LAN, a Wide Area Network (WAN), or a combination of both dedicated to providing connectivity between subnetworks in an Enterprise-wide network. |
| bandwidth | The bandwidth determines the rate at which information can be sent through a channel: the greater the bandwidth, the more information can be sent in a given amount of time. |
| bps (bits per second) | A measure of data transmission speed. |
| broadband personal communications standards (PCS) | Consists of 120 MHz of new spectrum available for new cellular networks. Also known as wideband PCS. |
| - C - | |
| CCITT | Consultative Committee for International Telegraph and Telephone. Now known as the International Telecommunications Union- Telecommunications Systems (ITU-TS). |
| CDMA | Code Division Multiple Access. Defines how a single channel can be allocated to support multiple users simultaneously. |
| CDPD | Cellular Digital Packet Data. |
| CDPD Forum | An industry trade association supporting the development of the Cellular Digital Packet Data (CDPD) commercial marketplace. |
| Cell | The geographic region in which Radio Frequency (RF) transmission from one fixed transmission site can be received at acceptable levels of signal strength using an omnidirectional or a directional antenna. In a cellular network, a cell represents a geographic area within which a particular bandwidth of radio frequency channels can be received at adequate signal strength. |
| Cellular Digital Packet Data (CDPD) | A wide-area, wireless data networking technology. CDPD is an open standard for using existing cellular networks for wireless data transmission. Packets of data are sent along channels of the cellular network. |
| cellular modems | A device that combines data modem and cellular telephone transceiver technologies in a single unit. This allows a user to transfer data on the cellular network without the use of a separate cellular telephone. |
| channel | A 30 kHz cellular voice channel. A voice-grade transmission facility with defined frequency response, gain, and bandwidth. Also, a path of communication, either electrical or electromagnetic, between two or more points. Also, channel is used to describe the distribution path into the market for value-added resellers. |
| circuit | The physical connection (or path) of channels, conductors and equipment between two given points through which an electric current may be established. Includes both sending and receiving capabilities. |
| circuit switched | The process of setting up and keeping a circuit open between two or more users, such that the users have exclusive and full use of the circuit until the connection is released. |
| CLNP | Connectionless Network Protocol. |
| CLNS | Connectionless Network Service. |
| clone | A mobile device, typically a cellular telephone, that claims to possess the same address identifier as another mobile device. |
| CMIP | Common Management Information Protocol [CCITT-X.711]. |
| CMIS | Common Management Information Service [CCITT-X.710]. |
| CMISE | Common Management Information Service Element. |
| code division multiple access (CDMA) | Defines how a single channel can be allocated to support multiple users simultaneously so that all mobile users transmit on the same frequency with different pseudo-random signals. Originally developed to support voice. One of two digital cellular standards in the US. |
| Comite Consultatif International Telegraphique et Telephonique (CCITT) | Consultative Committee for International Telegraph and Telephone. A standards organization that devises and proposes recommendations for international communications. Refer also to American National Standards Institute (ANSI). |
| compression | The removal of redundant or unnecessary information from a set of data. |
| confidentiality | A security process that ensures that the content of a transmitted message cannot be determined except by the possessor of a key associated with the message, even if the transmitted bits are observed. |
| connectionless network protocol (CLNP) | The standard OSI connectionless network protocol. |
| connectionless network service (CLNS) | An International Standards Organization (ISO) internetwork service. |
| COTS | Connection-Oriented Transport Service. |
| CRC | Cyclic Redundancy Check. These are used for the purposes of error detection. |
| CSMA/CD | Carrier Sense Multiple Access with Carrier Detection. |
| cyclic redundancy check (CRC) | A computational means to detect errors in frames transmitted between devices. The mathematical function is computed at the originating device before a frame is transmitted. Its numerical value is computed based on the content of the frame. This value is compared with a recomputed value of the function at the destination device. Refer also to Frame Check Sequence (FCS). |
| - D - | |
| data compression | Reducing the size of a file of data by eliminating unnecessary information, such as blanks and redundant data. |
| data encryption | The processing of data under a secret key so that the original data can only be determined by a recipient in possession of the secret key. |
| Data Link Layer | Layer 2 in the Open Systems Interconnect (OSI) 7-Layer Network Layer Reference Model. Provides communication among two or more systems. The Data Link Layer performs error checking, addressing, and other functions that are required to ensure accurate data transmission between adjacent systems. |
| datagram | A finite-length packet with sufficient information to be independently routed from source to destination. |
| decompression | The restoration of redundant data that was removed through compression. |
| decryption | The processing of received data by the possessor of a secret key in such a way that the intended contents of the data are restored. |
| decryption key | The secret key required to decrypt received data. |
| default route | A routing table entry which is used to direct any data addressed to any network numbers not explicitly listed in the routing table. |
| demultiplexing | The process of distributing data received in a shared data stream to the several entities that share the data stream. Demultiplexing can occur at several layers of a protocol stack. Refer to Multiplexing. |
| DES | Data Encryption Standard. An encryption/decryption algorithm defined in FIPS Publication 46. |
| Diffie-Hellman EKE | A procedure to exchange electronic keys between communicating devices. Used in CDPD. |
| Digital Sense Multiple Access With Collision Detection (DSMA/CD) | A technique used by Cellular Digital Packet Data (CDPD) to arbitrate access to the reverse channel stream by more than one Mobile End System (M-ES). |
| DNS | Domain Name System. |
| Domain Naming System (DNS) | A mechanism used in the Internet for translating names of host computers into addresses. It is a network database system that provides translation between host names and addresses. |
| - E - | |
| EHTD | Efficient Hyper Text Delivery: the component of the LEAP protocols which facilitates web browsing. |
| EMSD | Efficient Mail Submission & Delivery: the component of LEAP that addresses the Mobile Messaging application. EMSD is a messaging protocol that is highly optimized for the submission and delivery of short Internet e-mail messages. |
| EMSD-FS | EMSD Format Standard. EMSD-FS is a non-textual form of compact encoding of Internet e-mail (RFC-822) messages, which facilitates efficient message transfer. |
| EMSD-P | EMSD Protocol. EMSD-P is responsible for wrapping a limited size EMSD-FS message in a point-to-point envelope, and submitting or delivering it. |
| EMSD-SA | EMSD Server Agent. |
| EMSD-UA | EMSD User Agent. |
| encryption | The processing of data under a secret key in such a way that the original data can only be determined by a recipient in possession of the secret key. The process reduces the possibility of eavesdropping. |
| encryption key | The secret key used to perform the encryption process. |
| end system (ES) | Any computer not considered to be performing routing or bridging functions. In Internet terminology, an ES is a host; ESs are the actual physical and logical end nodes that exchange information. |
| end-to-end communications | Data delivered between a source and destination endpoint. |
| end-to-end connection | Connections between the source system and the destination system. |
| end-to-end data confidentiality | The provision of data confidentiality between the sender and receiver of a communication. |
| ESRO | Efficient Short Remote Operations: the efficient transport layer protocol for several LEAP applications. ESRO is a reliable connectionless transport mechanism, forming the foundation for the development of efficient protocols when TCP is too much and UDP is too little. |
| - F - | |
| file transfer protocol (FTP) | Common Internet file transfer program that uses Transmission Control Protocol/Internet Protocol (TCP/IP) |
| firewall | A security router that filters traffic based on addresses. |
| FPF | Free Protocols Foundation. FPF is an independent public forum, dedicated to the support of patent-free protocols. |
| frame | A Link Protocol Data Unit. |
| FTP | File Transfer Protocol. |
| full-duplex | Capability of simultaneously transmitting and receiving. |
| - G - | |
| gateway | A protocol conversion facility allowing connection of dissimilar communication systems. |
| GHz | GigaHertz, Hz x 109 (One million cycles per second). |
| Global Positioning System (GPS) | A system of satellites orbiting the earth used for navigation and location. Position on earth is determined by referencing multiple satellites in the system whose orbits are precisely known and thus provide a reference frame for measuring distances. |
| Global Standard For Mobile Communications (GSM) | A digital cellular standard used primarily in Europe and some other countries. Primarily a Time Division Multiple Access (TDMA) cellular voice service, though data services are offered over GSM. Formerly called Groupe Speciale Mobile. |
| GSM | Global Standard for Mobile communication. |
| - H - | |
| half-duplex | Capability of transmitting or receiving, but not both simultaneously. |
| handoff | The process of passing a Radio Frequency (RF) connection to another available channel either at the originating cell site, a neighboring cell site, or in another service provider's coverage area. As the subscriber moves from one location to another, the connection is continually handed off from channel to channel and from cell site to cell site. |
| host | The computer providing file transfer and communications services to client computers. |
| - I - | |
| ICMP | Internet Control Message Protocol. |
| IEEE | Institute for Electrical and Electronics Engineers. |
| IETF | Internet Engineering Task Force. |
| intermediate system (IS) | A node that is connected to more than one subnetwork with a primary role of forwarding data from one subnetwork to another. In Internet terminology, ISs are known as routers that relay data packets from ESs to their intended destinations. |
| International Standards Organization (ISO) | Organization that determines standards for international and national data communications. The US representative to the ISO is the American National Standards Institute (ANSI). |
| Internet | A set of networks using a set of network-independent protocols for communication that have been defined under the aegis of the Defense Advanced Research Projects Agency. |
| Internet (Internetwork) | (1) The global collection of interconnected local, mid-level, and wide-area networks that use Internet Protocol (IP) as the network layer protocol. (2) Any connection of two or more local or wide-area networks. |
| Internet Protocol (IP) | A connectionless protocol that requires no prior call setup between the source and destination systems. |
| IP | Internet Protocol. |
| IS | Intermediate System. |
| IS-95 | The CDMA (Code Division Multiple Access) standard. |
| ISO | International Standards Organization. |
| - J - | |
| - K - | |
| Kbps | Kilobits per second. |
| key | A quantity required for the execution of security algorithms that is intended to be used only by legitimate entities. |
| kHz | kiloHertz, Hz x 1000. |
| - L - | |
| LAN | Local Area Network. A network that takes advantage of the proximity of computers to offer relatively efficient, higher speed communications than long-haul or wide-area networks. Electronic mail, messaging, file sharing and database access are common LAN applications. |
| latency | The slight delay in data delivery through a network. |
| LEAP | Lightweight & Efficient Application Protocols. LEAP is a set of high-performance, efficient protocols which are ideal for mobile and wireless applications. |
| Location Directory (LD) | The repository of information specifying the current Forwarding Address of a collection of mobile hosts to be accessed by the redirectors. For Cellular Digital Packet Data (CDPD), refer to Mobile Network Location Protocol And Home Mobile Data Intermediate System. |
| - M - | |
| MAC | Medium Access Control. |
| MAC Layer | That layer of a distributed communications system concerned with the control of access to a medium that is shared between two or more entities. |
| message | A meaningful unit of information. A Protocol Data Unit (PDU) of defined format and purpose. Refers to the basic unit of data being transmitted. |
| Message Handling System (MHS) | A supplementary service that implements Message Store and Forward Message Handling. MHS is used within the Cellular Digital Packet Data (CDPD) network. MHS provides for distribution lists, return receipts and allows for gateways to proprietary message systems, including alternative delivery mechanisms such as telex or fax. |
| message transfer agent (MTA) | Performs Message Routing (e.g., to other MTAs) and message delivery to User Agents and Message Stores. |
| messaging API (MAPI) | An application protocol. |
| middleware | Software that isolates applications from the protocol requirements, hardware, and actual operations of a particular network. May perform protocol conversions between disparate systems. Refers to any software that resides between a client program and a server program. Middleware includes protocol stacks, network operating systems, and messaging systems. |
| MIME | Multipurpose Internet Mail Extensions. MIME is a specification for enhancing the capabilities of standard Internet e-mail. |
| modem | MOdulator-DEModulator. A device that translates computer information for transmission on both cellular and regular telephone lines. |
| modulation | The analog waveform of a transmitted digital signal. |
| Motorola Integrated Radio System (MIRS) | Technology developed by Motorola. ESMR is based on this technology. Nextel is the largest company deploying ESMR. (Now called iDEN). |
| MSC | Mobile Switching Center. |
| MTA | Message Transfer Agent. |
| MTS | Message Transfer System. |
| multicast | A one-way point to multi-point routing and relaying service that allows a message to be addressed and delivered to all members of a group, regardless of their current location. |
| multipath fading | The singal degradation that occurs when multiple copies of the same radio signal arrives at the receiver through different reflected paths. The interference of these signals, each having traveled a different distance, result in phase and amplitude variations. The radio signal processing in both the base station and mobile units have to be designed to tolerate a certain level of multipath fading. |
| multiplexing | The process of mixing data originating from several entities into a single shared data stream. Multiplexing can occur at several layers of a protocol stack. |
| - N - | |
| Network Protocol Data Unit (NPDU) | Network Layer Protocol Data Unit. The NPDU comprises the Network Layer Service Data Unit and the Network Layer Protocol Control Information. |
| Network Service Access Point (NSAP) | The NSAP is an abstraction of a point where the Network Layer service user and the Network Layer service provider meet. Each Network Entity may be accessed through one or more NSAPs by its users. Each NSAP has one or more NSAP-Addresses. |
| node | A node is an entity that participates in network communication. Examples of nodes are End Systems and Intermediate Systems. |
| NPDU | Network Protocol Data Unit. |
| NSAP | Network Service Access Point. |
| NSAP-Address | The NSAP-Address uniquely identifies a Network Service Access Point (NSAP). |
| NSAP-Selector | A component of an Network Service Access Point (NSAP)-Address used to select the Network Layer service user. The NSAP-Selector is sometimes referred to as a Transport-Selector; however, a user of the Network Layer need not be a transport service. |
| - O - | |
| open system | A system with publicly known protocols or architectures, one that requires no special protocols and is simple to implement. |
| Open Systems Interconnection (OSI) 7-Layer Network Layer Reference Model | An international standardization program facilitated by International Standards Organization (ISO) and Consultative Committee for International Telegraph and Telephone (CCITT) to develop standards for data networking that facilitate multivendor equipment interoperability. OSI includes the following seven layers: Physical Layer, Data Link Layer, Network Layer, Transport Layer, Session Layer, Presentation Layer, and Application Layer. |
| OSI | Open Systems Interconnection. A set of protocols designed to be an international standard method for connecting different types of computers and networks. Europe has done most of the work developing OSI. |
| OSI reference model | An "outline" of OSI that defines the seven layers of the model and their functions. Sometimes used to help describe other networks. Refer to Open Systems Interconnection (OSI) 7-Layer Network Layer Reference Model. |
| - P - | |
| packet | Network Protocol Data Unit |
| Patent-free protocol | A protocol which is functionally free from software patents. |
| PCS | Personal Communications Services. A wireless technology being developed in the US. Narrowband PCS refers to a new spectrum available for paging services. The digital signals of PCS are a series of rapid pulses, unlike analog's steady flow. |
| PDA | Personal Digital Assistant. |
| PDU | Protocol Data Unit. |
| Personal Communications Services (PCS) | Refers to the next generation of cellular systems. Will include data services. |
| Personal Digital Assistant (PDA) | A hand-held or custom-built Mobile End System (M-ES). |
| PGP | Pretty Good Privacy. PGP is a freeware software which is used worldwide for e-mail encryption and authentication including file encryption and peer-to-peer Virtual Private Network (VPN). |
| Physical Layer | Layer 1 in the Open Systems Interconnect (OSI) 7-Layer Network Layer Reference Model. That layer of a distributed communications system concerned with the actual transmission of data across a physical medium. The physical layer provides a physical connection for transmission of data between two data link entities. |
| ping | An ICMP message that is sent out to a known IP address. If the signal arrives at the known address, it returns to its point of origin, confirming connectivity. |
| point of presence | An entry point for connection into the network. |
| Point-to-Point Protocol (PPP) | An Internet protocol that provides a method for transmitting datagrams over serial point-to-point links. |
| PPP | Point to Point Protocol, |
| primitive | An abstraction representing the communication between layer entities operating at different layers or between a layer entity and the management entity controlling it. There are four types of primitives in the OSI (Open Systems Interconnection) model)-request, indication, response, and confirm. |
| protocol | A set of procedures for exchanging information between peer entities. A formal description of message formats and the rules two computers must follow to exchange those messages. Protocols can describe low-level details of machine-to-machine interfaces, such as the order in which bits are sent across wire, or high level exchanges between allocation programs, such as the manner in which two programs transfer files across the Internet. |
| Protocol Control Information (PCI) | The part of the Protocol Data Unit that contains addressing, control, flags, and optional information needed by peer Layer Service Providers to provide the service. Refer to protocol data unit and service data unit. |
| Protocol Data Unit (PDU) | The unit of information that is exchanged by peer Layer Service Providers to implement the protocol that offers the service. The PDU consists of a Protocol Control Information and Service Data Unit. |
| PSTN | Public Switched Telephone Network. Actual telephone wires. |
| public switched telephone network (PSTN) | Public telephone network. |
| - Q - | |
| QOS | Quality of service. |
| - R - | |
| radio frequency (RF) | The frequency in Hertz (cycles per second) of the carrier frequency being transmitted or received. |
| RDP | Reliable Data Protocol. |
| reassembly | The process of combining a number of the Link Layer Service Data Unit (LSDU) into an SN-Data Protocol Data Unit (PDU) or SN-Unitdata PDU. |
| Reed-Solomon code | A forward error correcting code used in Cellular Digital Packet Data (CDPD). |
| Reed-Solomon forward error correction | Refer to Reed-Solomon code. |
| reliable sequenced delivery | The delivery of a set of Protocol Data Units (PDUs) from a source to a destination with no errors in any PDU, in the order transmitted, and without gaps or duplicates. |
| RFC | The internet's Request for Comments documents series. The RFCs are working notes of the Internet research and development community. A document in this series may be on any topic related to computer communication, and may be anything from a meeting report to the specification of a standard. |
| RFC Publication | The mainstream of Internet publishing procedure, ensuring that the protocols are freely, easily and permanently accessible to anyone who wishes to use them. |
| RIP | Routing Interchange Protocol. A protocol which may be used on internets to pass routing information between gateways. It is used on many Local Area Networks (LANs) and on some of the NSFNET intermediate level networks. |
| roam | Traveling outside of a local cellular coverage area. |
| ROSE | Remote Operations Services Element. |
| router | A special-purpose dedicated computer that attaches to two or more networks and examines received packets from one network. Based on the destination address of the packet, forwards it to the most appropriate next network. |
| RPC | Remote Procedure Call: specified in RFC-1831 [89] and RFC-1833 [88] |
| - S - | |
| S/MIME | Secure MIME. S/MIME extends MIME and add security to the specification. |
| SAP-address | Service Access Point Address. |
| SNDCF | Subnetwork Dependent Convergence Function. |
| SDU | Service Data Unit. |
| secret key | A key whose value is not disclosed to unauthorized entities. |
| security | The set of functions concerned with ensuring that only authorized users of the network can use the network, and only in authorized ways. |
| segmentation | The process of fragmenting an SN-Data Protocol Data Unit (PDU) or SN-Unitdata PDU into a number of Link Service Data Units (LSDUs). |
| Serial Line Internet Protocol (SLIP) | A protocol used between a host and the service provider to transmit IP datagrams through a serial port. |
| Service Data Unit (SDU) | When a user of a layer service requests the Layer Service Provider to transfer data to a remote service user, the user data is termed a Service Data Unit. The Layer Service Provider attaches a small header, called the Protocol Control Information, to the user data. The combination of the Protocol Control Information and SDU is called a Protocol Data Unit. |
| SLIP | Serial Line Internet Protocol. |
| SNDCP | Subnetwork Dependent Convergence Protocol. A Network Layer protocol that supports subnetwork convergence. |
| SNMP | Simple Network Management Protocol. The Simple Network Management Protocol is the Internet's standard for remote monitoring and management of hosts, routers and other nodes and devices on a network. |
| Sockets Interface | The Sockets Interface, introduced in the early 1980s with the release of Berkeley UNIX, was the first consistent and well-defined application programming interface (API). It is used at the transport layer between Transmission Control Protocol (TCP) or User Datagram Protocol (UDP) and the applications on a system. Since 1980, Sockets has been implemented on virtually every platform. |
| specialized mobile radio (SMR) | (1) A wireless data service that operates in the 806 to 821 MHz and 851 to 866 MHz bands. (2) Analog trunked radio systems primarily used for dispatch applications. (3) Dispatch radio systems combined into the national ESMR network. |
| synchronization | The process of achieving a common interpretation of a transmitted bit stream between more than one entity at the same point in the bit stream. Synchronization may be required at each layer of a protocol stack. |
| synchronous | The communications method where characters are spaced by time, not by start and stop bits. Synchronous transmission of a message requires fewer bits and less time than asynchronous transmission. Refer to asynchronous. |
| - T - | |
| TCP | Transmission Control Protocol. A transport layer protocol for the Internet. A connection oriented stream protocol. |
| TCP/IP | Transmission Control Protocol/Internet Protocol. A set of protocols developed to link computers and data communications equipment across many kinds of networks. |
| TDMA | Time Division Multiple Access. |
| Telecommunications Industry Association (TIA) | Standards organization. |
| telemetry | A communications system for the transmission of short digital or analog data that monitors status information for a remote process, function or device. |
| Telnet | The virtual terminal access protocol used by the Internet. It allows a user at one site to interact with a remote timesharing system at another site as if the user's terminal was connected directly to the remote computer. |
| threshold | The minimum value of a signal that can be detected by the system or sensor under consideration. |
| throughput | The actual amount of useful and non-redundant information that is transmitted or processed. Throughput is the end result of a data call. Throughput is a measure of the efficiency of a communications link. |
| TIA | Telecommunications Industries Association. |
| Time Division Multiple Access (TDMA) | A medium access control scheme where each member of a device population is assigned transmission slots separated in time. |
| Transmission Control Protocol (TCP) | A connection-oriented protocol that provides reliable end-to-end service. Responsible for ensuring data integrity end-to-end, given that Internet Protocol (IP) is a connectionless protocol. |
| Transport Layer | Layer 4 in the Open Systems Interconnect (OSI) 7-Layer Network Layer Reference Model. Transpor Protocol 4 (TP4), Transmission Control Protocol (TCP) and User Datagram Protocol (UDP) reside at this layer. Connection-oriented service provides reliable and transparent transfer of data between cooperating session entities. |
| - U - | |
| UDP | User Datagram Protocol. |
| User Agent (UA) | Related to the messaging supplementary service. A user agent is an application entity that acts on behalf of a user and interfaces to a local message transfer agent. A user agent provides submission and delivery services and other message handling operations such as composing, forwarding/distributing, replying, examining. |
| User Datagram Protocol (UDP) | A connectionless protocol that provides end-to-end communication with fewer capabilities than Transmission Control Protocol (TCP). Each UDP datagram is handled independently. UDP does not guarantee delivery of data. |
| - V - | |
| vertical market application | An application that is industry-specific and typically very task-specific. Including systems for on-line reservations, point-of-sale, utility monitoring, or dispatch services. Such applications have been customized to meet the needs of a specific industry and its particular customers. |
| VMTP | Versatile Message Transaction Protocol |
| - W - | |
| WAN | Wide Area Network. A network that links a wide geographical area. |
| WAP | Wireless Application Protocol. WAP is a specification for wireless data communications using hand-held devices such as mobile phones and palmtop computers. |
| wide-area-network (WAN) | A network that links a wide geographical area. |
| window segment size | A parameter used to control the flow of data across a connection. |
| wireless | Communication by means of electromagnetic radiation, particular in the Radio Frequency (RF) portion of the spectrum. Can refer to various technologies for transmitting data, including those used by ARDIS, RAM, or Cellular Digital Packet Data (CDPD). |
| wireless data network | A radio-based network for data transmission. Cellular Digital Packet Data (CDPD) is an example. |
| WTP | Wireless Transaction Protocol |
| - X - | |
| X.25 | A network-level interface protocol and the underlying Link Layer protocols for connecting to a packet-switching network. Routes packets of data through a network to destination nodes. Used to connect remote terminals to host systems; provides any-to-any connections for simultaneous users. |
| - Y - | |
| - Z - | |