Instruction to ISDN
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Abbreviation of integrated services digital network, an international communications standard for sending voice, video, and data over digital telephone lines or normal telephone wires. ISDN supports data transfer rates of 64 Kbps (64,000 bits per second).
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Applications of ISDN
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Some applications of ISDN are..
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Internet Access
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ISDN is a fast, accurate, economical conduit for all kinds of Internet-based information, including global email, file transfer, news groups, bulletin boards and interactive applications. Emerging applications include electronic commerce and low-speed video and radio broadcasting. Net surfers can even cruise virtual malls to shop the world for goods and services in a convenient and secure sales environment.
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Telecommuting or Work-at-Home
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Both for full-time telecommuters and for those who work at home, ISDN supports fast, reliable LAN access, enhanced voice services, corporate email, file transfer, remote printing and all the other functions available to those that work in an office environment.
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Video Conferencing
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ISDN supports distance learning, business training, administrative conferencing and a wide range of other video-based applications with high fidelity audio and broadcast-quality, full color, full motion images. ISDN can be configured as set-top TV to PC, and PC to PC video conferencing at either 128 Kbps or 384 Kbps.
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Branch Office Communications
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ISDN provides high-performance, cost-effective connections for transferring information and linking your multiple business locations to create a fast, smooth-running Wide Area Network (WAN).
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Standby Inter-Networking
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ISDN can help you minimize the risks of outages or overflows by providing reliable, high-speed back up and extra bandwidth on a cost-effective, dial-up basis.
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Point-of-Sale Services
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ISDN delivers the speed and performance formerly associated only with costly private lines – at economical, public network prices. With ISDN, transaction times for processing credit card sales averages just four to six seconds. Compare that to analog telephone lines, which range from 30 to 60 seconds. That's especially important to queue-sensitive and high-volume retailers.
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Telemedia/Desktop Publishing
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ISDN offers the bandwidth and digital clarity to support such publishing-related functions as typesetting, processing color separations, creating printing plates, color scanning of photographs and page layout proofing. When turnaround speed is essential, ISDN is an ideal solution.
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Telemetry/Security
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With ISDN, a central surveillance site can visually observe numerous remote locations, while monitoring the status of alarms and access control devices.
The B channels provide connectivity for video and the D channel accommodates the other alarm inputs.
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channels of ISDN
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B Channel
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Operate at 64 Kbps. Carries information for user services including voice, audio,
video and digital data.
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D Channel
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Operate at 16 Kbps. Carries signals between the user and the network. This may also
carry user data packets.
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