Cisco Systems Planning Your Installation for Cisco VG350 Voice Gateway: Distance Limitations and Cable Types

Chapter 3 Planning Your Installation

Distance Limitations for Interface Cables

Cable Types

The cable types that are used are dependent on the Cisco VG350 Voice Gateway that you are using. For more information, see the “Interfaces and Service Capabilities” section on page 1-3and “Cable Specifications and Information” section on page A-1.

•GE cables (RJ-45 to RJ-45 straight-through cables)

•Analog voice cables (RJ-21)

Distance Limitations for Interface Cables

When planning your installation, consider distance limitations and potential electromagnetic interference (EMI) as defined by the Electronic Industries Association (EIA). Distance limitation information is included for the following VG ports:

•Gigabit Ethernet Maximum Distance, page 3-4

•FXS Analog Voice Port Maximum Distance, page 3-4

•FXS-E (Extended loop) Analog Voice Port Maximum Distance, page 3-4

Gigabit Ethernet Maximum Distance

The maximum segment distance for Gigabit Ethernet is 330 feet (100 meters) (specified in IEEE 802.3).

FXS Analog Voice Port Maximum Distance

The maximum distance is established by a total allowable loop resistance, including the phone or terminal equipment, of 600 ohms.

FXS-E (Extended loop) Analog Voice Port Maximum Distance

The maximum distance is established by a total allowable loop resistance, including the phone or terminal equipment, of 1400 ohms.

Note Typically, a 26 AWG wire is equal to 81.6 ohm/Kft and 24 AWG wire is equal to 51.3 ohm/Kft.

Cisco VG350 Voice Gateway Hardware Installation Guide

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