Page Comparison

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Hardware Compatibility Tool:    https://pathfinder.juniper.net/hct/model/?component=QFX-QSFP-DACBO-1M&tab=sPlatforms

QFX-QSFP-DACBO-1M  (40G to 4x 10G)   or    QFX-QSFP-DAC-1M ( 40G to 40G)

QSFP+ DAC Passive BreakOut Cable Specifications
DAC: direct-attach copper
Connector type: None. SFPs are permanently attached.
Length: 1 m

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http://www.juniper.net/techpubs/en_US/release-independent/junos/topics/reference/general/cable-ex-series-qsfp-plus-direct-attach.html

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