Record the protocol explicitly
A connector shell or advertised aggregate capacity does not establish Ethernet or InfiniBand operation. Identify the protocol and rate required at every endpoint before comparing products.
Check the port configuration
Record electrical lane count/rate, FEC, breakout mode and any auto-negotiation requirements from the specific platform's documentation. For a split assembly, identify each destination port independently.
Keep the release context
Read the compatibility and operating notes for the actual host hardware and firmware. A setting documented for one adapter generation or release is not a universal instruction. Preserve that context with the configuration so a later software change can be evaluated.
In practice / Worked example
Equal aggregate rate. Different optical lanes.
Complete both sides of the worksheet before treating two 200Gb/s labels as a match.
| Requirement | Endpoint A | Endpoint Z |
|---|---|---|
| Protocol / rate | Ethernet · 200Gb/s | Ethernet · 200Gb/s |
| Optical arrangement | 2 × 100G-PAM4 lanes | 4 × 50G-PAM4 lanes |
| Host electrical application | To be documented | To be documented |
| FEC / firmware / negotiation | To be documented | To be documented |
The optical arrangements differ; passive fiber does not convert signaling rates or combine lanes. NVIDIA documents a related limitation: its described 100G-PAM4 NDR optics cannot directly downshift to 50G-PAM4 HDR optics. Resolve the exact supported assembly or conversion from platform documentation. This illustrative worksheet establishes no WBN interoperability claim; electrical applications remain a separate check.
Source: NVIDIA · LinkX 100G-PAM4 overview ↗ Online reference checked 1 November 2026 · Backwards Compatibility
Before you specify
- Protocol at A and every Z
- Port mode, lane arrangement and FEC
- Host hardware and software revision
Sources & scope
General engineering guidance. External examples describe their own products and do not establish WBN availability or qualification.
- Firmware compatible products ↗ NVIDIA · ConnectX-6 · firmware 20.38.1002
- LinkX 100G-PAM4 product line overview ↗ NVIDIA · Online reference · accessed 1 Nov 2026