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Backbone Networks |
The backbone network is an important architectural element for building enterprise networks. It provides a path for the exchange of information between different LANs or subnetworks. A backbone can tie together diverse networks in the same building, in different buildings in a campus environment, or over wide areas. Generally, the backbone’s capacity is greater than the networks connected to it. |
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Backplane Architecture |
A backplane is a circuit board that includes peripheral connection slots into which I/O devices, processors, and other computer and networks components may be installed. The slots are connected to a high-speed communication bus or switching fabric that is controlled by an onboard processor and is also connected to onboard memory. A computer motherboard is the best example of a backplane, but other examples include backplanes in hubs, switches, and routers. There are various ways of implementing the bus architecture on a backplane in order to optimize performance. |
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Bandwidth |
Bandwidth is the information-carrying capacity of a communication channel. The channel may be analog or digital. Analog transmissions such as telephone calls, AM and FM radio, and television are measured in cycles per second (hertz or Hz); and digital transmissions are measured in bits per second. For digital systems, the terms “bandwidth” and “capacity” are often used interchangeably, and the actual transmission capabilities are referred to as the data transfer rate (or just data rate). |
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Bandwidth Management |
Bandwidth management is about making sure that enough bandwidth is available to meet traffic needs, and if not, managing the traffic in some way to ensure that critical traffic gets through. |
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Bandwidth on Demand |
Bandwidth on demand is a data communication technique for providing additional capacity on a link as necessary to accommodate bursts in data traffic, a videoconference, or other special requirements. The technique is commonly used on dial-up lines and wide area networks (WANs) to temporarily boost the capacity of a link. Bandwidth on demand is both economical and practical. It makes sense to use a switched line and only pay for services as they are needed, rather than lease an expensive dedicated line that may go underused part of the time. Networks such as frame relay can automatically provide more capacity without the need to add additional lines, but the capacity is limited by the size of the trunk that connects a customer to the frame relay network. |
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Baseband Network |
Baseband is a transmission method in which direct current pulses are applied directly to the cable to transmit digital signals. The discrete signal consists of either high- or low-voltage pulses that represent binary 1s and 0s or that hold binary information in encoded form. A base band network is usually limited to a local area. Ethernet is a baseband network that transmits only one signal at a time. The direct current signals placed on a baseband transmission system tend to degrade over distance due to attenuation and other factors. |
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Baud |
Baud is a measure of signal changes per second in a device such as a modem. It represents the number of times the state of a communication line changes per second. The name comes from the Frenchman Baudot, who developed an encoding scheme for the French telegraph system in 1877.Baud is rarely used to refer to modem speeds because it does not have a relationship to the number of bits transferred per second on high-speed modems. If a modem transferred 1 bit for every signal change, then its bits-per-second rate and baud rate would be the same. However, encoding techniques are employed to make 1 baud, or signal change, represent 2 or more bits. Two bits per baud is known as dibit encoding and 3 bits per baud is known as tribit encoding. |
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BGP (Border Gateway Protocol) |
BGP is a TCP/IP-based exterior routing protocol that is used between autonomous systems (ASs), primarily on the Internet. An AS is basically an Internet service provider in this context, although it defines any group of networks managed by a central authority. ASs are also referred to as domains. |
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B-ISDN (Broadband ISDN) |
ISDN (Integrated Services Digital Network) development began in the 1980s as part of a plan by the carriers to develop a single integrated network transmitting voice, video, and data communications. B-ISDN development began in 1988 as developers saw a need for bandwidth above 155 Mbits/sec in anticipation of future video and multimedia services. In general, ISDN is based on 64-Kbit/sec channels. These channels are just wide enough to handle a digitized voice call. ISDN is a switched service and is designed around intelligent switching components in the carrier network. It allows users to dial any other ISDN point on the network and create a high-speed digital link that can mimic point-to-point T1 lines. |
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Bluetooth |
Bluetooth is the code name of a wireless personal are a network specification that is being developed by the Bluetooth SIG(Special Interest Group).Bluetooth will enable electronic devices to spontaneously setup wireless networks with in small are as Bluetooth is designed for notebooks; telephones; and other devices, including wireless headsets ,handheld and wearable devices(such As inventory scanners),and data/voice access devices. |
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BOOTP (BOOT strap Protocol)
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BOOTP is an Internet protocol that can provide network configuration information to diskless workstations, or other workstations if necessary, on a local network. Diskless workstations need to obtain a boot image from a disk on the network because they do not have their own disks from which to obtain this information. BOOTP is also used to initialize IP phones. The boot image provides all the files required to start the operating system on the computer. |
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BRI (Basic Rate Interface)
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The basic rate interface is the minimal service obtainable for ISDN (Integrated Services Digital Network). ISDN is a digital phone service that is meant to replace the traditional analog phone system. BRI consists of two 64-Kbit/sec B channels and one 16-Kbit/sec D channel. Each B channel can carry a single digitized voice call or can be used as a data channel. The B channels can also be combined to form a single 128-Kbit/sec data channel. The D channel is used for call establishment and other signaling. |
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Bridges and Bridging
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Abridge is a LAN connection device with two or more ports that forwards frames from one LAN (local area network) segment to another. In the past, the bridge was a small box with several LAN connectors or a server with several network interface cards.
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Broadband Communications and Networking |
Broadband Communications and Networking Broadband communications is usually considered to be any technology with transmission rates above the fastest speed available over a telephone line. Broadband transmission systems typically provide channels for data transmissions in different directions . |
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Broadcast Networking
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Broadcast networking refers to a type of networking that is done on shared-media networks such as Ethernet where multiple nodes are attached to the same LAN. It is a one-to-many method of transmitting information. All the devices attached to the network that receive the broadcast are part of the same broadcast domain.
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Burst and Bursty Traffic
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A burst is a continuous transfer of data without interruption from one device to another. Microprocessors allow burst-mode block transfers of data to memory and onboard caches. Disk and network adapters perform burst-mode transfers in which they control the system bus in order to send multiple blocks of data. |
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Bus Topology
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The layout of a network’s cable system and the methods that workstations use to access and transmit data on the cable are part of the topology of a network. A bus topology network consists of a single cable trunk that connects one workstation to the next in a daisy-chain configuration .
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