4x100G DR4++ QSFP-DD Compatible Transceiver: 400G-QSFP-DD-12

The EdgeOptic 400G-QSFP-DD-12 is a multi-vendor compatible extended-reach DR4 (DR4++) QSFP-DD transceiver for 400 Gigabit Ethernet over parallel single-mode fiber. Four 100G lanes transmit at 1310 nm on separate fibers, each running at 106.25 Gbps with PAM4 modulation for an aggregate line rate of 425 Gbps. The same 10 km parallel-SMF reach class is sold under several names: Arista lists it as 400GBASE-PLR4, Cisco as 4x100G-LR (QDD-4X100G-LR-S), and the broader industry as DR4++. It extends reach well beyond the 500 m of standard 400GBASE-DR4 and the 2 km of DR4+.

Each of the four lanes uses an EML (Electro-absorption Modulated Laser) transmitter and a PIN photodiode receiver optimized for 1310 nm operation. Per-lane launch power runs 0 to +5 dBm with a minimum extinction ratio of 3.5 dB, and receiver sensitivity is −9 dBm per lane with an overload point of +5 dBm. The module carries a 9 dB optical path loss budget, supporting links up to 10 km over standard single-mode fiber. The 10 km reach class is a 100G Lambda MSA extension; the per-lane 100G-LR1 optics follow that MSA rather than the 500 m baseline defined by IEEE 802.3cd. Actual supportable distance depends on the loss of the deployed fiber plant, so verify the span loss against the 9 dB budget during planning.

The 400G-QSFP-DD-12 is a hot-pluggable QSFP-DD module with an MTP/MPO-12 APC optical interface. Eight fibers are active out of the twelve positions, four for transmit and four for receive. The APC (8-degree angled) end-face is mandatory: PAM4 per-lane signaling is sensitive to back-reflection, and UPC-polished MPO cords will degrade the link and cannot be mated to an APC port. The electrical interface conforms to the QSFP-DD MSA, and the 400G Ethernet MAC and electrical layer follow IEEE 802.3cd. Host-side RS(544,514) KP4 Forward Error Correction is required for correct link operation, with the FEC engine running in the host switch ASIC rather than in the module; FEC settings must match at both ends of the link.

DDM/DOM (Digital Diagnostic Monitoring) reports real-time per-lane transmit and receive optical power, module temperature, laser bias current, and supply voltage through the MSA management interface, so operators can watch transceiver health across all four lanes. CDR (Clock and Data Recovery) is implemented on the electrical lanes. The module operates over a 0 to 70 °C commercial temperature range with maximum power consumption of 14.5 W on a +3.3 V supply, which calls for adequate airflow in high-density QSFP-DD line cards. CE and RoHS marked, with Class 1 laser safety per FDA and IEC 60825-1.

Typical deployments include metropolitan data center interconnect, campus backbone, and inter-building links that need parallel-fiber reach beyond standard DR4. The four parallel lanes also support 400G to 4x100G breakout: an MPO-12 to four LC duplex fanout cable splits the module into four independent 100G connections. Each lane can terminate on a single-lane 100G host port whose reach matches the physical span, a 100GBASE-LR1 port for runs up to 10 km, a 100GBASE-FR1 port for runs up to 2 km, or a 100GBASE-DR port for runs up to 500 m. Match the far-end port to the actual span length, so a full 10 km run requires 100GBASE-LR1 receivers.

Backed by 15+ years of EdgeOptic compatibility engineering across vendor optical platforms, the 400G-QSFP-DD-12 can be coded for QSFP-DD host systems from major switch and router vendors. For platform coding requirements or volume quotes, contact our sales team. Made to order with a 2-week lead time and a lifetime warranty.