IBM Nways 8260, Руководство по установке

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E3/DS3 I/O Cards
The E3 I/O Card conforms with CCITT recommendation G.703 for the line interface at
34368 Kbps, and recommendation G.832 for the transportation mode.
The DS3 I/O Card conforms with ANSI recommendation T1.102-1993 for the line
interface at 44736 Kbps, and recommendations T1.107-1988/T1.107a-1990 for the
transportation mode.
The media for both I/O card types is a 75 ohm impedance coaxial pair with BNC
connectors for each direction of transmission.
Cabling Information
Table 6 details the accepted coaxial cables for the ATM ports.
Note: The 25 dB attenuation @ 400 MHz corresponds to an attenuation of 12 dB @
17 MHz, assuming that follows approximately a
√
f law.
For more information, refer to the IBM 8250 Multiprotocol Switching Hub, IBM 8260
Multiprotocol Intelligent Switching Hub, IBM 8285 Nways ATM Workgroup Switch,
Planning and Site Preparation Guide, GA33-0285, or the IBM 8265 Nways ATM Switch
Media Module Reference Guide, GA33-0460.
Table 6. Cabling Details
I/O Card Type Cable Type Impedance Attenuation
@ 400 MHz
E3 RG59 75 ohm 25dB MAX /
100m
DS3 RG59 75 ohm 25dB MAX /
100m
Cabling Distances
Because the maximum recommended distance depends on the quality of cable used,
the values given in Table 7 are approximate.
Table 7. ATM Device Cabling Distances
I/O Card Type: Cable Type Maximum Recommended Distance
E3 RG59 coax 100 meters (330 ft) based on a power budget of 12 dB
@ 17 MHz.
DS3 RG59 coax 68 meters (225 ft) default
135 meters (450 ft)
If cable distance exceeds 68 meters (225 ft), the default
configuration setting for the port must be changed. See
the
WAN Module User's Guide, SA33-0396.
Appendix A. Technical Information
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