Juniper QFX5100, Руководство по оборудованию

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CHAPTER 9
Cable Specifications
• Cable Specifications for QSFP+ Transceivers on page 89
• Cable Specifications for Console and Management Connections for the QFX
Series on page 91
•
Understanding QFX Series Fiber-Optic Cable Signal Loss, Attenuation, and
Dispersion on page 91
• Calculating the Fiber-Optic Cable Power Budget for a QFX Series Device on page 93
•
Calculating the Fiber-Optic Cable Power Margin for a QFX Series Device on page 93
Cable Specifications for QSFP+ Transceivers
The 40-Gigabit Ethernet QSFP+ transceivers that connect Node devices to Interconnect
devices in a QFabric system use 12-ribbon multimode fiber crossover cable with female
MTP connectors. The fiber can be either OM3 or OM4. These cables are not sold by Juniper
Networks.
CAUTION: To maintain agency approvals, use only a properly constructed,
shielded cable.
TIP: Ensure that you order cables with the correct polarity. Vendors refer to
these crossover cables as key up to key up or latch up to latch up. If you are
using patch panels between two QSFP+ transceivers, ensure that the proper
polarity is maintained through the cable plant.
Table 34 on page 89 describes the signals on each fiber. Table 35 on page 90 shows the
pin to pin connections for proper polarity.
Table 34: QSFP+ MTP Cable Signals
Signal Fiber
Tx0 (Transmit) 1
Tx1 (Transmit) 2
89 Copyright © 2014, Juniper Networks, Inc.