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Troubleshooting Wireless Networks

  • modem error-correcting protocols

    The protocols that modems agree on and use for checking and correcting transmission errors have evolved toward accuracy, speed, and efficiency since 1978 when the Xmodem protocol became a de facto standard. Continue Reading

  • datagram

    A datagram is, to quote the Internet's Request for Comments 1594, "a self-contained, independent entity of data carrying sufficient information to be routed from the source to the destination computer without reliance on earlier exchanges between ... Continue Reading

  • poison reverse

    In a computer network that uses the Routing Information Protocol (RIP) or other distance vector routing protocols, a poison reverse is a way in which a gateway node tells its neighbor gateways that one of the gateways is no longer connected. Continue Reading

  • Sequenced Packet Exchange (SPX)

    SPX (Sequenced Packet Exchange) is the protocol for handling packet sequencing in a Novell NetWare network. Continue Reading

  • Link Control Protocol (LCP)

    In the Point-to-Point Protocol (PPP), the Link ControlProtocol (LCP) establishes, configures, and tests data-link Internet connections. Continue Reading

  • FG-D (Feature Group D)

    FG-D (Feature Group D) is a type of telecommunication trunk used to provide "equal access" capability from telecommunication carriers and central offices (where the switching equipment is located and customer lines are connected and terminated) to ...Continue Reading

  • WebNFS

    WebNFS is a product and proposed standard protocol from Sun Microsystems that extends its Network File System (NFS) to the Internet.Continue Reading

  • Gigabit Ethernet

    Gigabit Ethernet, a transmission technology based on the Ethernet frame format and protocol used in local area networks (LANs), provides a data rate of 1 billion bits per second (one gigabit). (Continued...)Continue Reading

  • COFDM

    COFDM is a modulation scheme that divides a single digital signal across 1,000 or more signal carriers simultaneously.Continue Reading

  • Multicast Dissemination Protocol (MDP)

    The Multicast Dissemination Protocol (MDP) is a communications protocol for one-to-many transmissions in wired or wireless networks.Continue Reading

  • Ymodem

    Ymodem is an error-correcting protocol for a modem that uses larger data blocks for greater efficiency.Continue Reading

  • Common Management Information Protocol (CMIP)

    Common Management Information Protocol (CMIP) is a network management protocol built on the Open Systems Interconnection (OSI) communication model.Continue Reading

  • SCTP (Stream Control Transmission Protocol)

    SCTP (Stream Control Transmission Protocol) is a protocol for transmitting multiple streams of data at the same time between two end points that have established a connection in a network.Continue Reading

  • EIGRP (Enhanced Interior Gateway Routing Protocol)

    EIGRP (Enhanced Interior Gateway Routing Protocol) is a network protocol that lets routers exchange information more efficiently than with earlier network protocols.Continue Reading

  • Quad FastEthernet (QFE)

    Quad FastEthernet (QFE) is a network interface card (NIC) manufactured by Sun Microsystems that is designed to enhance the bandwidth of a Peripheral Component Interconnect (PCI)-based server using Sun Microsystem's Solaris 8 or later operating ...Continue Reading

  • RSVP (Resource Reservation Protocol)

    RSVP (Resource Reservation Protocol) is a set of communication rules that allows channels or paths on the Internet to be reserved for the multicast (one source to many receivers) transmission of video and other high-bandwidth messages.Continue Reading

  • PPPoE (Point-to-Point Protocol over Ethernet)

    PPPoE (Point-to-Point Protocol over Ethernet) is a specification for connecting multiple computer users on an Ethernet local area network to a remote site through common customer premises equipment, which is the telephone company's term for a modem ...Continue Reading

  • foreign network

    In the Mobile Internet Protocol (Mobile IP), a foreign network is any network other than the home network to which a mobile device may be connected.Continue Reading

  • UUCP (UNIX-to-UNIX Copy Protocol)

    UUCP (UNIX-to-UNIX Copy Protocol) is a set of UNIX programs for copying (sending) files between different UNIX systems and for sending commands to be executed on another system.Continue Reading

  • sliding windows (windowing)

    Sliding windows, a technique also known as windowing, is used by the Internet's Transmission Control Protocol (TCP) as a method of controlling the flow of packets between two computers or network hosts.Continue Reading

  • foreign agent

    In Mobile Internet Protocol (Mobile IP), a foreign agent is a router serving as a mobility agent for a mobile node.Continue Reading

  • Next Hop Resolution Protocol (NHRP)

    In a computer network, the Next Hop Resolution Protocol (NHRP) is a protocol or method that can be used so that a computer sending data to another computer can learn the most direct route (the fewest number of hops) to the receiving computer.Continue Reading

  • Media Gateway Control Protocol (MGCP)

    Media Gateway Control Protocol (MGCP), also known as H.248 and Megaco, is a standard protocol for handling the signaling and session management needed during a multimedia conference.Continue Reading

  • Reverse Address Resolution Protocol (RARP)

    RARP (Reverse Address Resolution Protocol) is a protocol by which a physical machine in a local area network can request to learn its IP address from a gateway server's Address Resolution Protocol (ARP) table or cache.Continue Reading

  • FDDI (Fiber Distributed Data Interface)

    FDDI (Fiber Distributed Data Interface) is a set of ANSI and ISO standards for data transmission on fiber optic lines in a local area network (LAN) that can extend in range up to 200 km (124 miles).Continue Reading

  • MBone (Multicast Internet)

    The MBone, now sometimes called the Multicast Internet, is an arranged use of a portion of the Internet for Internet Protocol (IP) multicasting (sending files - usually audio and video streams - to multiple users at the same time somewhat as radio ...Continue Reading

  • NAK (negative acknowledgment or not acknowledged)

    NAK is an abbreviation for negative acknowledgment or not acknowledged.Continue Reading

  • Hot Standby Router Protocol (HSRP)

    Hot Standby Router Protocol (HSRP) is a routing protocol that allows host computers on the Internet to use multiple routers that act as a single virtual router, maintaining connectivity even if the first hop router fails, because other routers are ...Continue Reading

  • Broadband Integrated Services Digital Network (BISDN)

    BISDN is both a concept and a set of services and developing standards for integrating digital transmission services in a broadband network of fiber optic and radio media.Continue Reading

  • COPS (Common Open Policy Service Protocol)

    COPS (Common Open Policy Service Protocol) is a proposed standard protocol for exchanging network policy information between a policy decision point (PDP) in a network and policy enforcement points (PEPs) as part of overall Quality of Service (QoS) ...Continue Reading

  • round-trip time (RTT)

    Round-trip time (RTT), also called round-trip delay, is the time required for a signal pulse or packet to travel from a specific source to a specific destination and back again...(Continued)Continue Reading

  • Technical Office Protocol (TOP)

    Technical Office Protocol (TOP), also called Technical and Office Protocol, is a set of protocols intended for networks that perform distributed information processing in business offices... (Continued)Continue Reading

  • DEN (Directory-Enabled Networking)

    Directory-Enabled Networking (DEN) is an industry-standard initiative and specification for how to construct and store information about a network's users, applications, and data in a central directory.Continue Reading

  • FireWire

    FireWire is Apple Computer's version of a standard, IEEE 1394, High Performance Serial Bus, for connecting devices to your personal computer.Continue Reading

  • VTAM (Virtual Telecommunications Access Method)

    VTAM (Virtual Telecommunications Access Method) is an IBM application program interface (API) for communicating with telecommunication devices and their users.Continue Reading

  • HomeRF (home radio frequency)

    HomeRF (for home radio frequency) is a home networking standard developed by Proxim Inc.Continue Reading

  • SDLC (Synchronous Data Link Control)

    (SDLC is also an abbreviation for systems development life cycle.Continue Reading

  • Bearer Independent Call Control (BICC)

    Bearer Independent Call Control (BICC) is a signaling protocol based on N-ISUP that is used to support narrowband ISDN service over a broadband backbone network without interfering with interfaces to the existing network and end-to-end services.Continue Reading

  • DVMRP (Distance Vector Multicast Routing Protocol)

    DVMRP (Distance Vector Multicast Routing Protocol) is the oldest routing protocol that has been used to support multicast data transmission over networks.Continue Reading

  • Fast Ethernet

    Fast Ethernet is a local area network (LAN) transmission standard that provides a data rate of 100 megabits per second (referred to as "100BASE-T").Continue Reading

  • TP0-TP4 (transport protocols 0 to 4)

    TP0-TP4 (transport protocols 0 to 4) are the five protocols in the Transport layer of the Open Systems Interconnection (OSI) model for telecommunication.Continue Reading

  • IPX (Internetwork Packet Exchange)

    IPX (Internetwork Packet Exchange) is a networking protocol from Novell that interconnects networks that use Novell's NetWare clients and servers.Continue Reading

  • BYE packet

    A BYE (or Goodbye) packet is a type of Real-Time Transport Control Protocol (RTCP) packet that is sent when a participant in a multicast event leaves the session.Continue Reading

  • spanning tree protocol (STP)

    Spanning tree protocol (STP) is a Layer 2 network protocol used to prevent looping within a network topology. The protocol allows two bridges to exchange information for only one bridge to handle a given message sent between two computers within the...Continue Reading

  • Dynamic Source Routing (DSR)

    Dynamic Source Routing (DSR) is a self-maintaining routing protocol for wireless networks. The protocol can also function with cellular telephone systems and mobile networks with up to about 200 nodes. A Dynamic Source Routing network can configure ...Continue Reading

  • X.25

    The X.25 protocol, adopted as a standard by the Consultative Committee for International Telegraph and Telephone (CCITT), is a commonly-used network protocol.Continue Reading

  • GARP (Generic Attribute Registration Protocol)

    GARP (Generic Attribute Registration Protocol) is a local area network (LAN) protocol that defines procedures by which end stations and switches can register and de-register attributes, such as network identifiers or addresses, with each other...Continue Reading

  • policy-based networking

    Policy-based networking is the management of a network so that various kinds of traffic - data, voice, and video - get the priority of availability and bandwidth needed to serve the network's users effectively.Continue Reading

  • sniffer

    In common industry usage, a sniffer (with lower case "s") is a program that monitors and analyzes network traffic, detecting bottlenecks and problems.Continue Reading

  • source quench

    Using the Internet Control Message Protocol (ICMP), a source quench is a message from one host computer to another telling it to reduce the pace at which it is sending packet to that host.Continue Reading

  • Source Quench Introduced Delay (SQuID)

    Also see SQUID, a UNIX-based program for caching Web pages and other Internet content closer to the user.Continue Reading

  • Network Job Entry (NJE)

    Network Job Entry (NJE) is an application designed for the transfer of commands, messages, programs, and jobs among different computing systems in a network.Continue Reading

  • n-tier

    An n-tier application program is one that is distributed among three or more separate computers in a distributed network.Continue Reading

  • NBMA (non-broadcast multiple access)

    NBMA (non-broadcast multiple access) is one of four network types in the OSPF (Open Shortest Path First) communications protocol.Continue Reading

  • Nagle's algorithm

    Named for its creator, John Nagle, the Nagle algorithm is used to automatically concatenate a number of small buffer messages; this process (called nagling) increases the efficiency of a network application system by decreasing the number of packets...Continue Reading

  • running disparity (RD)

    Running disparity (RD or rd) is the difference between the number of logic 1 bits and logic 0 bits between the start of a data sequence and a particular instant in time during its transmission.Continue Reading

  • response time

    According to the IBM Dictionary of Computing (which cites International Organization for Standardization Information Technology Vocabulary as the source), response time is: The elapsed time between the end of an inquiry or demand on a computer ...Continue Reading

  • FCAPS (fault-management, configuration, accounting, performance, and security)

    FCAPS is a network management framework created by the International Organization for Standardization (ISO). FCAPS categorizes the working objectives of network management into five levels. The five levels are:  fault-management (F), the ...Continue Reading

  • connectionless

    In telecommunication, connectionless describes communication between two network end points in which a message can be sent from one end point to another without prior arrangement.Continue Reading

  • circuit-switched

    Circuit-switched is a type of network in which a physical path is obtained for and dedicated to a single connection between two end-points in the network for the duration of the connection.Continue Reading

  • DTE (Data Terminal Equipment)

    In computer data transmission, DTE (Data Terminal Equipment) is the RS-232C interface that a computer uses to exchange data with a modem or other serial device.Continue Reading

  • Intelligent Network (IN)

    Intelligent Network (IN) is a telephone network architecture originated by Bell Communications Research (Bellcore) in which the service logic for a call is located separately from the switching facilities, allowing services to be added or changed ...Continue Reading

  • DCE (Distributed Computing Environment)

    In network computing, DCE (Distributed Computing Environment) is an industry-standard software technology for setting up and managing computing and data exchange in a system of distributed computers.Continue Reading

  • duplex

    In telecommunication, duplex communication means that both ends of the communication can send and receive signals at the same time.Continue Reading

  • XDMA (Xing Distributed Media Architecture)

    XDMA (Xing Distributed Media Architecture) is a network architecture for multicast streaming media transmissions.Continue Reading

  • dumb network

    A dumb network is one that provides the physical interconnection between nodes but not much processing to support signaling.Continue Reading

  • SDH (Synchronous Digital Hierarchy)

    SDH (Synchronous Digital Hierarchy) is a standard technology for synchronous data transmission on optical media.Continue Reading

  • corporate area network (CAN)

    A corporate area network (CAN) is a separate, protected portion of a corporation's intranet.Continue Reading

  • connection-oriented

    In telecommunications, connection-oriented describes a means of transmitting data in which the devices at the end points use a preliminary protocol to establish an end-to-end connection before any data is sent.Continue Reading

  • ring

    A ring is a network topology or circuit arrangement in which each device is attached along the same signal path to two other devices, forming a path in the shape of a ring.Continue Reading

  • NetBIOS (Network Basic Input/Output System)

    NetBIOS (Network Basic Input/Output System) is a program that allows applications on different computers to communicate within a local area network (LAN).Continue Reading

  • Service Location Protocol (SLP)

    The Service Location Protocol (SLP) is a protocol or method of organizing and locating the resources (such as printers, disk drives, databases, e-mail directories, and schedulers) in a network.Continue Reading

  • run book

    In a computer system or network, a run book is a written set of procedures for the routine and exceptional operation of the system or network by an administrator or operator.Continue Reading

  • IP addressing and subnetting fundamentals

    Our IP addressing and subnetting crash course provides an overview of IP addressing-related topics network engineers need to know, including IPv4 and IPv6, subnetting, DHCP, and calculating subnet masks. For more in-depth information, visit our ...Continue Reading

  • 10BASE-T

    10BASE-T, one of several physical media specified in the IEEE 802.3 standard for Ethernet local area networks (LANs), is ordinary telephone twisted pair wire.Continue Reading

  • 100BASE-T

    In 100 Mbps (megabits per second) Ethernet (known as Fast Ethernet), there are three types of physical wiring that can carry signals: 100BASE-T4 (four pairs of telephone twisted pair wire) 100BASE-TX (two pairs of data grade twisted-pair wire) ...Continue Reading

  • high-speed dialup

    High-speed dialup, sometimes advertised as broadband dialup, is an Internet service provider (ISP) feature that speeds up data transfer by using a special server, called an acceleration server, to act as a bridge between the user's dialup connection...Continue Reading

  • Asynchronous Pulsed Radiated Incident Light

    Asynchronous Pulsed Radiated Incident Light is a multi-duplicitous communication protocol (MDCP) used to configure wireless local area networks (WLANs) on the fly.Continue Reading

  • 32-bit IP addressing

    32-bit IP addressing is the IP address scheme used in Internet Protocol 4 (IPv6 uses a 128-bit system)... (Continued)Continue Reading

  • graceful degradation

    Graceful degradation is the ability of a computer, machine, electronic system or network to maintain limited functionality even when a large portion of it has been destroyed or rendered inoperative. The purpose of graceful degradation is to prevent ...Continue Reading

  • bottleneck

    A bottleneck is a stage in a process that causes the entire process to slow down or stop. In a communications context, a bottleneck is a point in the enterprise where the flow of data is impaired or stopped entirely... (Continued)Continue Reading

  • TCP/IP troubleshooting: A structured approach -- Introduction

    This tip from WindowsNetworking.com describes a structured approach for troubleshooting connectivity problems with TCP/IP networks. This is the first of a series of articles on TCP/IP troubleshootingContinue Reading

  • CompTIA Security+ exam overview

    An overview of the CompTIA Security+ exam overview including some basic facts about the exam and some analysis and perspectives of the exam.Continue Reading

  • disruption-tolerant network (DTN)

    A disruption-tolerant network (DTN) is a network designed so that temporary or intermittent communications problems, limitations and anomalies have the least possible adverse impact... (Continued)Continue Reading

  • Wireless network security best practices

    Don't let your wireless LAN (WLAN) jeopardize your corporate networks, servers and data. In this guide, you'll discover how to mitigate the risks WLAN pose and learn how to perform vulnerability assessments to manage potential risks.Continue Reading

  • star network

    A star network is a local area network (LAN) in which all nodes (workstations or other devices) are directly connected to a common central computer.Continue Reading

  • email response management service (ERMS)

    An email response management service (ERMS) is a set of programs that automatically handles email messages and attachments according to user-defined rules... (Continued)Continue Reading

  • Introduction -- Chapter 1 of 'Network Analysis, Architecture and Design'

    This chapter introduces the analysis, architecture, and design processes. Described are the fundamental concepts of the processes of network analysis, architecture, and design; systems and services; as well as their characteristics and prepares the ...Continue Reading

  • wideband

    Wideband is a transmission medium or channel that has a wider bandwidth than one voice channel (with a carrier wave of a certain modulated frequency).Continue Reading

  • WATS (wide-area telephone service)

    WATS (wide-area telephone service) is a specialized form of fixed-rate long-distance telecommunication service.Continue Reading

  • TDMA (time division multiple access)

    TDMA (time division multiple access) is a technology used in digital cellular telephone communication that divides each cellular channel into three time slots in order to increase the amount of data that can be carried. (Continued...)Continue Reading

  • out-of-band signaling

    Out-of-band signaling is telecommunication signaling (exchange of information in order to control a telephone call) that is done on a channel that is dedicated for the purpose and separate from the channels used for the telephone call.Continue Reading

  • digital loop carrier (DLC)

    DLC also is an abbreviation for Data Link Control.Continue Reading

  • E-carrier system

    To see the relationship between the E-carrier system, the T-carrier system, and DS0 multiples, see digital signal X. E1 (or E- is a European digital transmission format devised by the ITU-TS and given the name by the Conference of European Postal ...Continue Reading

  • committed information rate (CIR)

    committed information rateContinue Reading

  • carrier-to-noise ratio (CNR or C/N)

    In communications, the carrier-to-noise ratio, often written CNR or C/N, is a measure of the received carrier strength relative to the strength of the received noise.Continue Reading

  • microwave

    The term microwave refers to electromagnetic energy having a frequency higher than 1 gigahertz (billions of cycles per second), corresponding to wavelength shorter than 30 centimeters.Continue Reading

  • in-band signaling

    In the public switched telephone network, (PSTN), in-band signaling is the exchange of signaling (call control) information on the same channel that the telephone call itself is using.Continue Reading

  • baseband

    Describes a telecommunication system in which information is carried in digital form on a single unmultiplexed signal channel on the transmission medium.Continue Reading

  • band

    In telecommunication, a band - sometimes called a frequency band - is a specific range of frequencies in the radio frequency (RF) spectrum, which is divided among ranges from very low frequencies (vlf) to extremely high frequencies (ehf).Continue Reading

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