| A | B |
|---|
| 10BaseT | Ethernet LAN designed to run on UTP cabling. 10BaseT runs at 19 megabits per second. The maximum length for the cabling between the NIC and the hub (or switch, repeater, etc.) is 100 meters. It uses baseband signaling. No industry standard spelling exists, so sometimes written 10BASE-T or 10 Base-T. |
| 100BaseT | Generic term for an Ethernet cabling system designed to run at 100 megabits per second on UTP cabling. It uses baseband signaling. No industry standard spelling exists, so sometimes written 100BASE-T or 100Base-T |
| 1000BaseT | Gigabit Ethernet on UTP |
| activity light | A light that turns on when the card detects network traffic, so it makes an intermittent flickering when operating properly |
| administrator account | User account, created when the OS is first installed, that is allowed complete, unfettered access to the system without restriction |
| Automatic Private IP Addressing (APIPA) | Feature of Windows that automatically assigns an IP address to the system when the client cannot obtain an IP address automatically. |
| bandwidth | Piece of the spectrum occupied by some form of signal, such as television, voice, fax data. Signals require a certain size and location of bandwidth to be transmitted. The higher the bandwidth, the faster the signal transmission, allowing for a more complex signal such as audio or video. Because bandwidth is a limited space, when one user is occupying it, others must wait their turn. Bandwidth is also the capacity of a network to transmit a given amount of data during a given period |
| bus topology | Network configuration wherein all computers connect to the network via a central bus cable. |
| client | Computer program that uses the services of another computer program. Software that extracts information from a server; your auto-dial phone is a client, and the phone company is its server. Also, a machine that accesses shared resources on a server |
| client/server network | Network that has dedicated server machines and client machines. |
| coaxial cable | Cabling in which an internal conductor is surrounded by another, outer conductor, thus sharing the same axis. |
| crossover cable | Special UTP cable used to connect hubs or to connect network cards without a hub. Crossover cable reverse the sending and receiving wire pairs from one end to the other |
| cyclic redundancy check (CRC) | Very accurate mathematical method used to check for errors in long streams of transmitted data. Before data is sent, the main computer uses the data to calculate a CRC value form the data’s contents. If the receiver calculates a CRC value different from the received data, the data was corrupted during transmission and is re-sent. Ethernet packets have a CRC code. |
| default gateway | In a TCP/IP network, the nearest router to a particular host. This router’s IP address is part of the necessary TCP/IP configuration for communication with multiple networks using IP. |
| destination port | A fixed, predetermined number that defines the function or session type |
| directory service | Centralized index that each PC accesses to locate resources in the domain |
| domain-based network | Network that eliminates the need for logging in to multiple servers by using domain controllers to hold the security database for all systems |
| domain name service (DNS) | TCP/IP name resolution system that translates a host name into an IP address |
| dynamic host configuration protocol (DHCP) | Protocol that enables a DHCP server to set TCP/IP settings automatically for a DHCP client. |
| ephemeral port | An arbitrary number generated by the sending computer; the receiving computer uses the ephemeral port as a destination address so that the sending computer knows which application to use for the returning packet. They usually fall in the 1024-5000 range, but this varies slightly among the different operating systems. |
| Ethernet | Name coined by Xerox for the first standard of network cabling and protocols. Based on a bus topology. |
| full-duplex | Any device that can send and receive data simultaneously |
| hardware protocol | Defines many aspects of a network, from the packet type to the cabling and connectors used. |
| hub | Electronic device that sits at the center of a star topology network, providing a common point for the connection of network devices. Hubs repeat all information out to all ports and have been replaced by switches, although the term is still commonly used |
| hybrid topology | Combine aspects of the other topologies to capitalize on their strengths and minimize their weaknesses. |
| IP address | Numeric address of a computer connected to the Internet. An IPv2 address is made up of 4 octets of 8-bit binary numbers translated into their shorthand numeric values. An IPv6 address is 128 bits long. The IP address can be broken down into a network ID and a host ID. Also called Internet address |
| IPCONFIG | Command-line utility for Windows servers and workstations that displays the current TCP/IP configuration of the machine. Similar to WINIPCFG and IFCONFIG. |
| IPX/SPX | Internetwork Packet Exchange/Sequenced Packet Exchange. Communication protocol that is speedy, works well with routers, and takes up relatively little RAM when loaded. Although once popular, it has all but disappeared in favor of TCP/IP. |
| link lights | the term all network techs use in place of the terms lights, or LEDs |
| loopback plug | Device used during loopback tests to check the female connector on a NIC |
| media access control (MAC) address | Unique 48-bit address assigned to each network card. TEEE assigns blocks of possible addresses to various NIC manufacturers to help ensure that the address is always unique. The Data Link layer of the OSI model uses MAC addresses for locating machines |
| mesh topology | Network topology where each computer has a dedicated ling to every other computer, most often used in wireless networks |
| NET command | Command in Windows that allows users to view a network without knowing the names of the other computers on that network |
| NetBIOS Extended User Interface (NetBEUI) | The default protocol for Windows for Workgroups, LANtastic, and Windows 95. Offers small size, easy configuration, and a relatively high speed, but it can’t be used for routing. its inability to handle routing limits NetBEUI to networks smaller than about 200 nodes. |
| network interface card (NIC) | Expansion card that enables a PC to physically link to a network |
| network operating system (NOS) | Standalone operating system or part of an operating system that provides basic file and supervisory services over a network. Although each computer attached to the network has its own OS, the NOS describes which actions are allowed by each user and coordinates distribution of networked files to the user who requests them |
| NSLOOKUP | Command-line program in Windows used to determine exactly what information the DNS server is providing about a specific host name |
| packets | Basic component of communication over a network. Group of bits of fixed maximum size and well-defined format that is switched and transmitted as a single entity through a network. Contains source and destination address, data, and control information. |
| peer-to-peer network | Network in which each machine can act as both a client and a server |
| PING | stands for packet Internet groper. Slang term for a small network message (ICMP ECHO) sent by a computer to check for the presence and aliveness of another. Used to verify the presence of another system. Also the command used at a prompt to ping a computer |
| port | 16-bit numbers between 0 and 65,535, assigned to a particular TCP/IP session. Are used to determine, not only the kind of session, but also how to get the packet or response back to the sending computer. |
| resources | Data and services of a PC |
| RJ-11 | The connector that hooks your telephone to the telephone jack |
| RJ-45 | The standard for UTP connectors |
| ring topology | Network configuration wherein all computers connect to the network via a central ring of cable |
| router | Device connecting separate networks; forwards a packet from one network to another based on the network address for the protocol being used. For example, an IP router looks only at the IP network number Routers operate at Layer 3 (Network) of the OSI seven-layer model. |
| server | Computer that shares its resources, such as printers and files, with other computers on a network. Example: Network File System Server that shares its disk space with a workstation that does not have a disk drive of its own. |
| shielded twisted pair (STP) | Cabling for networks, composed of pairs of wires twisted around each other at specific intervals. Twists serve to reduce interference (also called crosstalk)—the more twists, the less interference. Cable has metallic shielding to protect the wires form external interference |
| star topology | Network topology where the computers on the network connect to a central wiring point, usually called a hub |
| static IP address | Manually set IP address that will not change |
| subnet mask | Value used in TCP/IP settings to divide the IP address of a host into its component parts: network ID and host ID. |
| switch | Device that filters and forwards traffic based on some criteria. a bridge and a router are both examples of switches. |
| TCP/IP | Communication protocols developed by the U.S. Department of Defense to enable dissimilar computers to share information over a network |
| TRACERT | Command- line utility used to follow the path a packet takes between two hosts. Also called TRACEROUTE |
| universal naming convention (UNC) | The combining of the names of the resource being shared and the system sharing. The UNC is distinguished by its use of double backslashes in front of the sharing system’s name and a single backslash in front of the shared resource’s name |
| unshielded twisted pair (UTP) | Popular type of cabling for telephone and networks, composed of pairs of wires twisted around each other at specific intervals. The twists serve to reduce interference. The more twists, the less interference. Unlike its cousin, STP, UTP cable has no metallic shielding to protect the wires from external interference. 1000BaseT uses UTP, as do many other networking technologies |
