QDD-400G-SR4.2-BD – 400G SR4.2 QSFP-DD – MPO-12 MMF – 100m OM4
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QDD-400G-SR4.2-BD Description
QDD-400G-SR4.2-BD is a Cisco 400GBASE-SR4.2 QSFP-DD optical transceiver for short-reach 400GE data center links over parallel multimode fiber. It supports native 400GE links and up to 4 x 100GE breakout to QSFP-100G-SR1.2 modules, uses four MMF pairs with an MPO-12 UPC connector, reaches up to 100 m over OM4 MMF, and follows IEEE 802.3bm plus 400GAUI-8/CEI-56G-VSR-PAM4 signaling for BOMs that need Cisco SR4.2 optics rather than LC or single-mode modules.
Quick Specs
|
Parameter |
Specification |
|---|---|
|
Product ID |
QDD-400G-SR4.2-BD |
|
Product type |
400GBASE-SR4.2 QSFP-DD optical transceiver |
|
Form factor |
QSFP-DD |
|
Ethernet rate |
400 Gigabit Ethernet |
|
Breakout support |
Up to 4 x 100GE breakout |
|
Peer breakout optic |
QSFP-100G-SR1.2 |
|
Connector type |
MPO-12 UPC |
|
Fiber type |
Multimode fiber |
|
Reach on OM3 |
70m |
|
Reach on OM4 |
100m |
|
Reach on OM5 |
150m |
|
High-speed electrical interface |
400GAUI-8/CEI-56G-VSR-PAM4 |
|
Maximum power consumption |
12 W |
Application Scenarios
Use QDD-400G-SR4.2-BD when the planned 400G link uses MPO-12 multimode cabling and the physical path fits Cisco’s documented OM3, OM4, or OM5 reach. This keeps the optic aligned with a parallel MMF patching design instead of an LC or single-mode design.
This transceiver can be used for 4 x 100GE breakout to QSFP-100G-SR1.2 modules. Review the Cisco platform, software release, breakout policy, and far-end modules before the order is released, especially in ACI fabric or access-port deployments.
Keep QDD-400G-SR4.2-BD separate from LC BiDi, SR8, DR4, FR4, and LR4 inventory. The names are close in purchasing systems, but the connector, fiber media, reach, and peer-optic requirements are not interchangeable.
Product Comparison
|
Parameter |
QDD-400G-SR4.2-BD |
QDD-400G-BD |
QDD-400G-SR8-S | |
|---|---|---|---|---|
|
Product type |
400GBASE-SR4.2 QSFP-DD transceiver |
400G QSFP-DD BiDi transceiver |
400GBASE-SR8 QSFP-DD transceiver |
400GBASE-DR4 QSFP-DD transceiver |
|
Connector type |
MPO-12 UPC |
LC UPC |
MPO-16 APC |
MPO-12 APC |
|
Fiber type |
Multimode fiber |
Multimode fiber |
Multimode fiber |
Single-mode fiber |
|
Cable topology |
Parallel MMF |
Duplex MMF |
Parallel MMF |
Parallel SMF |
|
Native link reach |
70m OM3; 100m OM4; 150m OM5 |
50m OM3; 70m OM4; 100m OM5 |
70m OM3; 100m OM4 |
500m |
|
Breakout capability |
4 x 100GE to QSFP-100G-SR1.2 |
100G operating mode documented |
2 x 200GE or 8 x 50GE |
4 x 100G to QSFP28 100G-DR, QSFP-100G-FR, or QSFP-100G-LR |
|
Nominal data rate |
425 Gbps |
425 Gbps |
425 Gbps |
425 Gbps |
|
High-speed electrical interface |
400GAUI-8/CEI-56G-VSR-PAM4 |
8 x 26.5625GB PAM4 400GAUI-8 |
400GAUI-8/CEI-56G-VSR-PAM4 |
400GAUI-8/CEI-56G-VSR-PAM4 |
|
Maximum power consumption |
12 W |
12 W |
12 W |
12 W |
- QDD-400G-SR4.2-BD is the MPO-12 multimode option when the order needs Cisco 400G SR4.2 reach and optional 4 x 100GE breakout.
- QDD-400G-BD uses duplex LC multimode cabling, so it belongs in a different patch-panel plan from SR4.2 MPO links.
- QDD-400G-DR4-S and QDD-400G-FR4-S are single-mode choices for longer reach requirements and should not be substituted into an MMF bill of materials.
- For breakout projects, confirm the Cisco port mode and QSFP-100G-SR1.2 peer optics before checking price, order, support entitlement handling, or deployment timing. Related SKU checks: QDD-400G-SR8-S.
Selection Guide
1. Choose it for MPO-12 multimode links
Select this SKU when the physical design calls for a Cisco 400G QSFP-DD optic over parallel MMF and the link budget fits 70m on OM3, 100m on OM4, or 150m on OM5.
2. Validate the breakout endpoint
For 4 x 100GE breakout, use the documented QSFP-100G-SR1.2 peer optics and verify that the Cisco platform and software release support the required breakout behavior.
3. Separate it from LC and single-mode optics
Do not approve QDD-400G-SR4.2-BD as a simple replacement for QDD-400G-BD, DR4, FR4, or LR4 optics. The connector and fiber media change the cabling, patching, and remote module requirements.
4. Confirm platform support before purchase
Check the exact Cisco switch, router, line card, QSFP-DD port, and software release in Cisco compatibility documentation before the purchasing team requests a final quote.
Ordering Checklist
|
Check Item |
What to Confirm |
Why It Matters |
|---|---|---|
|
Exact Product ID |
QDD-400G-SR4.2-BD |
Prevents substitution with BD, SR8, DR4, FR4, or LR4 optics |
|
Host compatibility |
Cisco platform, line card, QSFP-DD port, and software release |
Confirms the optic is supported in the intended device |
|
Fiber plant |
MPO-12 UPC multimode cabling |
SR4.2 is not a duplex LC or single-mode optic |
|
Fiber grade and distance |
OM3 up to 70m, OM4 up to 100m, or OM5 up to 150m |
Keeps the planned link inside Cisco’s documented reach |
|
Breakout peer optics |
QSFP-100G-SR1.2 modules for 4 x 100GE breakout |
Aligns the remote 100G ports with Cisco’s documented breakout path |
|
Remote 400G optic |
Matching Cisco-supported 400G SR4.2 optic for native 400GE links |
Avoids a connector, wavelength, or media mismatch |
Specifications
| Parameter | Specification | Parameter | Specification |
|---|---|---|---|
| Product ID | QDD-400G-SR4.2-BD | Product type | 400GBASE-SR4.2 QSFP-DD optical transceiver |
| Form factor | QSFP-DD | Ordering description | 400G QSFP-DD Transceiver, MPO-12 UPC, 100m OM4 MMF, 400GBASE-SR4.2, Can be used for 4X breakout to QSFP-100G-SR1.2 |
| Supported Ethernet rate | 400 Gigabit Ethernet | Breakout support | Up to 4 x 100GE breakout |
| Peer breakout optic | QSFP-100G-SR1.2 | Connector type | MPO-12 UPC |
| Fiber type | Multimode fiber | Fiber pairs | Four pairs of MMF |
| Fiber core size | 50 micron | Modal bandwidth | 2000 MHz*km on OM3; 4700 MHz*km on OM4 and OM5 |
| Reach on OM3 | 70m | Reach on OM4 | 100m |
| Reach on OM5 | 150m | Nominal data rate | 425 Gbps |
| High-speed electrical interface | 400GAUI-8/CEI-56G-VSR-PAM4 | Signal lane structure | Four parallel fiber pairs with two 50Gbps bidirectional wavelengths per fiber |
| Wavelengths | 855 nm and 908 nm | Average transmit power per lane | -6.2 to +4 dBm |
| Average receive power per lane | -8.2 to +4 dBm | Maximum supported insertion loss | 1.9 dB |
| Pre-FEC bit error ratio | 2.4 x 10^-4 | Maximum power consumption | 12 W |
| Pull tab color | Gray | Module operating temperature | 0 to 75 degrees C |
| Storage temperature | -40 to 85 degrees C | Laser class | Class 1 |
| Compliance reference | RoHS 6 | Standard warranty | 5 years |
Get More Information
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