Juniper EX9214

opcal modules or cables. Your JTAC engineer will likely request that you check the
third-party opcal module or cable and, if required, replace it with an equivalent
Juniper-qualied component.
Use of third-party opcal modules with high-power consumpon (for example,
coherent ZR or ZR+) can potenally cause thermal damage to or reduce the lifespan of
the host equipment. Any damage to the host equipment due to the use of third-party
opcal modules or cables is the users’ responsibility. Juniper Networks will accept no
liability for any damage caused due to such use.
The Gigabit Ethernet SFP, SFP+, and QSFP+ transceivers and the 100GBASE-LR4 CFP transceivers
installed in EX9200 switches support digital opcal monitoring (DOM): You can view the diagnosc
details for these transceivers by issuing the operaonal mode CLI command show interfaces diagnostics
optics.
Overview of EX Series Switches: Fiber-Opc Cable Signal Loss,
Aenuaon, and Dispersion
IN THIS SECTION
Signal Loss in Mulmode and Single-Mode Fiber-Opc Cable | 138
Aenuaon and Dispersion in Fiber-Opc Cable | 139
To determine the power budget and power margin needed for ber-opc connecons, you need to
understand how signal loss, aenuaon, and dispersion aect transmission. EX Series switches use
various types of network cables, including mulmode and single-mode ber-opc cable.
Signal Loss in Mulmode and Single-Mode Fiber-Opc Cable
Mulmode ber is large enough in diameter to allow rays of light to reect internally (bounce o the
walls of the ber). Interfaces with mulmode opcs typically use LEDs as light sources. However, LEDs
are not coherent light sources. They spray varying wavelengths of light into the mulmode ber, which
reects the light at dierent angles. Light rays travel in jagged lines through a mulmode ber, causing
signal dispersion. When light traveling in the ber core radiates into the ber), higher-order mode loss
(HOL) occurs. (Cladding consists of layers of lower-refracve index material in close contact with a core
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