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CHAPTER 3
Installation Guidelines and Requirements
3-8
Cabling Recommendations
You may want to consult the document GR-63 (LSSGR, FD-15): Network
Equipment Building System (NEBS) Requirements: Physical Protection,
Issue 1, October 1995 for additional cable recommendations.
Comply with the following recommendations:
• Use only shielded cables.
• Ensure that cable distance and rate limits meet IEEE-recommended
maximum speeds and distances for signaling purposes. For
information about attenuation and power loss in optical fiber cables
see:
> ANSI T1.646a-1997 Telecommunications – Broadband ISDN -
Physical Layer Specification for User-Network Interfaces Including
DS1/ATM (1997)
> ANSI T1.646-1995 Telecommunications – Broadband ISDN -
Physical Layer Specification for User-Network Interfaces Including
DS1/ATM (1995)
> AT&T (Lucent) Technical Note Power Margin Analysis (November
1995)
• Ensure that power cables deliver sufficient power to the system.
• Attach laser fiber connectors only to Class 1 laser devices in
accordance with IEC 825-1, Safety of Laser Products - Part 1.
• Route cables so that they do not restrict ventilation or airflow.
• Route cables so that modules and field-replaceable units are easily
accessible.
• Route cables in a logical direction to prevent loss of connectivity to
other equipment in the rack, associated equipment in adjacent racks,
or to the backbone network.
• Consider using cable-management brackets to keep network cables
untangled and orderly and to prevent cables from hindering access to
other slots.
• For specifications on cables for line modules, see Chapter 12, Module
Specifications.