Q1: What is a QSFP-DD-400G-DR4 module?
A: The QSFP-DD-400G-DR4 is a QSFP-DD form-factor transceiver supporting 400 Gbps Ethernet over single-mode fiber (SMF) via four parallel lanes, each carrying a PAM4-modulated 100 Gbps optical channel at 1310 nm with an MPO-12 connector.
Q2: What is the maximum transmission distance supported?
A: Up to 500 m over G.652 single-mode fiber when host-side FEC (e.g., KP4) is enabled.
Q3: Which connector and fiber type does it use?
A: Uses an MPO-12 connector over 8-strand or more 9/125 µm SMF.
Q4: Is QSFP-DD-400G-DR4 compatible across equipment brands?
A: Yes. It is MSA-compliant and compatible with Cisco, Arista, Juniper, Huawei, Edge-Core, ProLabs, FS.com, and other vendors whose hardware supports generic QSFP-DD optics.
Q5: Can this module be hot-swapped?
A: Yes. As a QSFP-DD module, it supports hot-plug insertion and removal without powering down the device.
Q6: Does QSFP-DD-400G-DR4 support breakout into lower speeds?
A: Yes. It supports 4×100G DR1 breakout or 2×200G DR2 breakout (via host-side capability) using appropriate MPO-to-LC or MPO-to-MPO breakout cables.
Q7: Does it support digital diagnostics (DDM/DOM)?
A: Yes. It supports CMIS / SFF-8636 / SFF-8679 diagnostic monitoring, with real-time data via I²C for optical power, temperature, voltage, and module status.
Q8: What is the data rate per lane?
A: Supports up to 100 Gbps per lane (PAM4, 106.25 Gbps per lane), aggregating to ~425 Gbps optical bandwidth over 4 lanes.
Q9: What is typical power consumption?
A: Approximately < 10 W to max ~12 W, depending on vendor and temperature variant.
Q10: What is the operating temperature range?
A: Standard commercial modules support 0 °C to 70 °C; extended variants may go to –5 °C to +85 °C, and industrial versions to –40 °C to +85 °C.
Q11: Which standards does it comply with?
A: Compliant with IEEE 802.3bs (400GBASE-DR4), QSFP-DD MSA, 400GAUI-8 / CEI-56G-VSR-PAM4, and diagnostic protocols CMIS V4.0 / SFF-8636 / SFF-8679.
Q12: How can I verify compatibility with my equipment?
A: Ensure your system supports QSFP-DD 400G DR4 optics and allows third-party modules. Many vendors provide compatibility matrices and part-number coding. Generic MSA-compliant modules typically work across major platforms.
Q13: What are typical application scenarios?
A: Suitable for 400 GbE data center spine-leaf interconnects, rack-to-rack links, high-density multimode deployments, and use in breakout to lower-rate 100G or 200G connections.
Q14: What is the optical power budget per lane?
A: Typical transmit power per lane: –2.9 to +4.0 dBm; receiver sensitivity: ≥ –5.9 dBm, allowing ~3 dB link budget for 500 m reach over SMF.