QSFP+ Direct Attach Copper Cables for EX Series Switches

Quad small form-factor pluggable plus (QSFP+) direct attach copper (DAC) cables are suitable for in-rack connections between QSFP+ ports of EX Series switches. They are suitable for short distances of up to 16.4 ft (5 m), making them ideal for highly cost-effective networking connectivity within a rack and between adjacent racks. 

Macroreer Juniper QFX-QSFP-DAC-1M, Passive 1 meter , QSFP+ to QSFP+ TWINAX 40Gbase-CR4, 100% Juniper compatible ( $39.99)
Reference Link: http://amzn.to/2ac8ani

Cable Specifications

QSFP+ passive DAC cables are hot-removable and hot-insertable. A cable consists of a cable assembly that connects directly into two QSFP+ modules, one at each end of the cable. The cables use integrated duplex serial data links for bidirectional communication and are designed for data rates up to 40 Gbps. Passive DAC cables have no signal amplification built into the cable assembly.

Table 1 describes the support for QSFP+ passive DAC cable lengths on EX Series switches for Junos OS releases.

QFX-QSFP-DAC-1M	Rate	40-Gbps full-duplex serial transmission
	Connector type	Copper pigtail
	Supply voltage	3.3 V
	Power consumption (per end)	0.015 W
	Storage temperature	–40° C through 85° C
	Cable type	Twinax
	Wire AWG	30 AWG
	Minimum cable bend radius	2.54 cm (1 in.)
	Cable characteristic impedance	100 ohms
	Crosstalk between pairs	1% maximum
	Time delay	4.3 nsec/ft
	Length	3.28 ft (1 m)