Enginer

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Troubleshooting Cable Access Networks
Session 2904

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© 2000, Cisco Systems, Inc.

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Agenda
• Specifications and References • RF Troubleshooting • DOCSIS Troubleshooting • Cisco IOS ® and Cable • Upconverter Troubleshooting • CMTS Troubleshooting • CMTroubleshooting
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• Questions
© 2000, Cisco Systems, Inc.

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Functional Components
Five Major Parts to a Cable TV Network
TV HFC HFC (Hybrid (Hybrid Fiber Fiber Coax) Coax)

• Headend • The trunk cable

TAP TAP Distribution LHE Receiver Receiver Regional Head End Fiber Modulator Modulator and Scrambler and Scrambler Local Head Down End Stream Trunks

• The distribution(or feeder) cable in neighborhoods • The drop cable to the home

For each channel Receiver Modulator and Scrambler Up Stream Fiber Node

Other Sources

LHE HFC Interface

Bidirectional Amplifiers

• The terminal equipment (TV, cable modem, set-top box, etc)

To Internet
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© 2000, Cisco Systems, Inc.

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Reference Material

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Web Resources
Check CCO resources for:
• DDTS issues
http://www.cisco.com/support/bugtools/

• Downloading latest images
http://www.cisco.com/kobayashi/sw-center/sw-ios.shtml

• Documentation
http://www.cisco.com/univercd/cc/td/doc/product/cable/ index.htm

• Release Notes
http://www.cisco.com/univercd/cc/td/doc/product/software/ios113ed/ios113p/cablern/index.htm

• TAC Tips
http://www.cisco.com/kobayashi/serv_tips.shtml
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References
Web References
• http://www.cisco.com/cable • http://www.cablemodem.com • http://www.cablelabs.com • http://www.scte.org • http://cable.doit.wisc.edu • http://www.catv.org • http://www.wwwgsolutions.com • http://www.hukk.com

TextReferences
• Modern Cable Television Technology— Video, Voice, and Data Communications By Walter Ciciora/James Farmer/ David Large ISBN # 1-55860-416-2 • Broadband Return Systems for Hybrid Fiber/Coax Cable TV Networks By Donald Raskin and Dean Stoneback ISBN # 0-13-636515-9 • Cable Television Proof-Of-Performance By Jeff Thomas ISBN # 0-13-306382-8

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White Paper Resources
• Multimedia Traffic Engineering for Cable Networks
http://www.cisco.com/warp/public/cc/cisco/mkt/access/ apath/tech/hfcn_wp.pdf

• Combined Wisdom on the Upstream
http://www.cisco.com/warp/public/cc/cisco/mkt/access/ apath/tech/mllt_wp.pdf

• Successfully Deploying Data Over Cable Networks: An Overviewhttp://www.cisco.com/warp/public/cc/cisco/mkt/servprod/ tech/dcsis_wp.pdf

• Business Case for Two-Way Service Deployment over HFC Network
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http://www.cisco.com/warp/public/cc/cisco/mkt/servprod/ tech/2way_pl.pdf
© 2000, Cisco Systems, Inc.

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International Split Plans
Region or Country North, Central, and South America, China, Korea, Phillipines, Thailand, Singapore Australia Japan, New Zealand India, Malta,Eastern Europe Western Europe, Ireland, United Kingdom
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Split Plan 40/52

65/85 55/70 30/48 65/85

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Is Your Upstream DOCSIS Compliant?
Variable Frequency Range Carrier to Noise (upstream) Transit Delay (Map Advance) Carrier to hum Amplitude Ripple Group Delay Ripple Digital Signal Levels From Cable Modem (Upstream)
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DOCSIS Specification 5–42 MHz Edge to Edge Not less than 25 dB £ 0.800 msec Not greater than -23 dBc (7.0%) 5–42 MHz: .5 dB/MHz 5–42 MHz: 200 ns/MHz DOCSIS Specifications +8 to +58 dBmV (QPSK) +8 to +55 dBmV (16-QAM)

Your Plant Settings

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Specs for Success
Typical DOCSIS Per Upstream Bandwidth*
Upstream Bandwidth 200 kHz 400 kHz 800 kHz 1600 kHz 3200 kHz...