I manage an older 1 Gb/s network, and we're getting a multi-gigabit wireless bridge to test between two buildings. I'd like to stress-test the connection and measure its actual throughput, but we don't have spare switches or laptops with built-in 10 Gb/s networking that can easily be used for a temporary setup. What would be the cheapest and simplest way to connect a couple of devices at each end and generate enough traffic to test the link?
4 Answers
A practical option is to buy two inexpensive office desktops and add compatible 10 Gb network cards. Put one at each building, connect them to the bridge, and run iperf3 between them. Used desktops and network cards can be fairly cheap compared with dedicated test equipment.
Thunderbolt 3 or Thunderbolt 4 10 Gb Ethernet adapters can work well if you already have suitable laptops. Pair one adapter with a laptop at each end and use iperf3, but make sure the laptops, drivers, cables, and adapter interface can actually sustain the target speed.
The right hardware depends on the bridge interfaces. Check whether it uses 5GBASE-T copper, 10GBASE-T, or SFP+. That determines whether you need USB or Thunderbolt Ethernet adapters, transceivers, or regular 10 Gb network cards. Once the devices are connected, iperf3 is usually the simplest measurement tool.
Use iperf3 on both ends. It’s free, easy to run, and designed specifically for measuring network throughput. Start one device in server mode and connect to it from the other device as a client. You may need multiple parallel streams to fully saturate a fast link.

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