I manage an older 1 Gb/s network, and we're preparing to test a faster wired-and-Wi-Fi bridge between two buildings. I'd like to push enough traffic across the connection to measure its real throughput, but we don't currently have spare switches or laptops with 10 Gb/s network interfaces for a temporary setup. What's the simplest and least expensive way to build two test endpoints and measure the link speed?
4 Answers
Thunderbolt 3 or 4 to 10 Gb/s Ethernet adapters can work if you already have compatible laptops. Just make sure the adapters match the bridge interfaces—such as 10GBASE-T or SFP+—and tune iperf3 appropriately, since one stream may not fully load a fast link. The exact cheapest option depends on what connectors the bridge provides.
Use iperf3 on both endpoints. Start it in server mode on one device and connect from the other with the client mode. It can generate traffic and report throughput, retransmits, and other useful details.
If the goal is to model normal usage rather than only find the maximum bandwidth, testing with several ordinary laptops at once could be more representative. For a quick capacity check, though, two properly equipped systems and iperf3 should be much easier.
The usual low-cost setup is two inexpensive office desktops, one at each end, with a suitable 10 Gb/s network card installed in each. Run a throughput test between them rather than involving your production equipment.

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