Post on 03-Apr-2018
7/28/2019 Unidad IV Sistema de Cable
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2006 Cisco Systems, Inc. All rights reserved.
Implementing Secure
Converged Wide AreaNetworks (ISCW)
Module 2: Teleworker Connectivity
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Module 2:
TeleworkerConnectivity
Lesson 2.2: Describing Cable Technology
7/28/2019 Unidad IV Sistema de Cable
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2006 Cisco Systems, Inc. All rights reserved.
Objectives
Describe the components of a typical cable system.
Identify the benefits of a cable system.
Explain how cable uses a part of RF electromagneticfrequencies to transmit.
7/28/2019 Unidad IV Sistema de Cable
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2006 Cisco Systems, Inc. All rights reserved.
What is a Cable System?
CATV originally meant community antenna television. This formof transmission shared TV signals.
Cable systems were originally built to extend the reach of TVsignals and improve over-the-air TV reception.
Modern cable systems use fiber and coaxial cable for signaltransmission.
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2006 Cisco Systems, Inc. All rights reserved.
Cable Technology Terms
Broadband
CATV
Coaxial cable
Tap
Amplifier
HFC
Downstream
Upstream
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Cable System Components
Subscriber Drops
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Cable System Benefits
Cable is cost-effective because broadcast architecture
is cascaded to users.
Cable supports different services:
Analog video
Digital video
Voice
Data
Inexpensive high-speed Internet access enables the
application of advanced SOHO and teleworkerdeployments.
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Digital Signals over Radio Waves
Cable uses a part of RF electromagnetic frequencies.
Cable can transmit signals simultaneously in either direction.
RF portion used is subdivided for the two paths:
Downstream: Headend-to-subscriber has 810 MHz of RF bandwidth.
Upstream: Subscriber-to-headend has 37 MHz of RF bandwidth.
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DOCSIS
DOCSIS is a standard for certification of cable
equipment vendor devices (cable modem and cablemodem termination system).
DOCSIS specifies the physical and MAC layers.
DOCSIS defines RF interface requirements for a data-over-cable system.
Cable equipment vendors must pass certificationconducted by CableLabs.
Euro-DOCSIS is a variation adapted for use in Europe.
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Summary
Modern cable systems provide two-way communication
between subscribers and the cable operator. Cableoperators now offer customers advancedtelecommunications services including high-speedInternet access, digital cable television, and residential
telephone service. Cable systems support telephony and data services
and analog and digital video services.
DOCSIS defines the communications and operation
support interface requirements for a data-over-cablesystem and permits the addition of high-speed datatransfer to an existing CATV system.
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Q and A
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Resources
DOCSIS
http://www.cablemodem.com/specifications
Broadband Cable
http://www.cisco.com/en/US/customer/tech/tk86/tsd_technology_support_category_home.html
CableLabs
http://www.cablelabs.com/
http://www.cablemodem.com/specificationshttp://www.cisco.com/en/US/customer/tech/tk86/tsd_technology_support_category_home.htmlhttp://www.cisco.com/en/US/customer/tech/tk86/tsd_technology_support_category_home.htmlhttp://www.cablelabs.com/http://www.cablelabs.com/http://www.cisco.com/en/US/customer/tech/tk86/tsd_technology_support_category_home.htmlhttp://www.cisco.com/en/US/customer/tech/tk86/tsd_technology_support_category_home.htmlhttp://www.cablemodem.com/specifications7/28/2019 Unidad IV Sistema de Cable
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