JNP-100G-DAC-xM-BCC | Juniper Compatible QSFP to QSFP Copper Direct-Attach 100GBASE-CR4 Cable | 1 to 5M

Q: Will this work in place of the Juniper JNP-100G-DAC-1M?
A: Yes. This cable is a direct replacement for the JNP-100G-DAC-1M. It uses the same QSFP28 form factor, 100GBASE-CR4 standard, and 103.1 Gbps aggregate data rate. It will plug-and-play in any Juniper switch with QSFP28 100G ports, with no configuration changes required.

Q: Which Juniper platforms support this cable?
A: This cable works in any Juniper platform with QSFP28 100G Ethernet ports that support 100GBASE-CR4. This includes switches and routers with QSFP28 interfaces compliant with IEEE 802.3bj. If your equipment accepts the original JNP-100G-DAC-1M, this cable will function identically.

Q: What is the difference between passive and active 100G DAC cables, and when should I use passive?
A: Passive DAC cables use copper conductors only, with no signal conditioning electronics. They draw negligible power (<0.2W) and cost less, but are limited to 5 meters maximum. Active cables include signal amplifiers and can reach 7 meters or more but consume 1 to 2 watts and add cost. For distances up to 5 meters, passive cables like this one are preferred for lower power, lower cost, and zero added latency.

Q: Does this cable require forward error correction (FEC) to operate reliably?
A: 100GBASE-CR4 is defined with Clause 91 RS-FEC (Reed-Solomon Forward Error Correction) as part of the IEEE 802.3bj specification. Most QSFP28 host interfaces enable RS-FEC automatically when a 100GBASE-CR4 cable is detected. This is standard behaviour and does not require manual configuration. The cable will interoperate with any compliant QSFP28 port.

Q: Can I mix cable lengths in the same switch, and will the four lanes operate independently?
A: Yes. Each 100G DAC cable is an independent physical link. You can use 1m, 3m, and 5m cables in different ports on the same switch without any interaction. The four 25G lanes within a single cable are bonded together and always operate as a single 100G link, but separate cables operate completely independently. Lane skew compensation is handled by the QSFP28 MSA specification within each cable.