Advice Needed: Demonstrating a Passive QSFP Module with Limited Testing Equipment

Hi everyone,

I’m an electrical engineering student currently interning at a small hardware company specializing in specialty network equipment. For my final project, I’m developing a passive QSFP module that routes high-speed QSFP lanes to connectors. The module includes only an EEPROM to store basic module data (e.g., type and settings).

For my university presentation, I can’t use the company’s testing equipment outside the company. To demonstrate basic functionality, I’m considering using my university’s oscilloscope (limited to 500 MHz bandwidth) and a second-hand QSFP PCI network card. Since the oscilloscope can’t handle the full 25 gbit/s I plan to limit data transfer speeds to under 1 Gbps. This won’t showcase the full potential of the module but should suffice as proof of concept.

I hope to use the second-hand QSFP network card as a host to generate test traffic. My question is: can a QSFP network card generate traffic autonomously without being connected to a network? Will it recognize the passive module via the EEPROM and attempt to send traffic? Is it possible to set the QSFP network card to a arbitrary slow speed than full 25 gbit/s?

To provide more context, my module is purely passive, with no active processing or response capabilities. I have some experience with Linux but little exposure to professional networking hardware.

Any advice on whether this setup is feasible or suggestions for alternative solutions would be greatly appreciated.

Thank you!

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