iperf3 vs Shadow
iperf3
software.es.netShadow
shadow.github.ioSide by side
| Figure | iperf3 | Shadow |
|---|---|---|
| Price from | Free | — |
| Free plan | Yes | — |
| Free trial | — | — |
| Open source | — | — |
| macOS | Yes | — |
| Linux | Yes | Yes |
| API | Yes | — |
| Self-hosted | Yes | — |
| Plans published | 1 | 0 |
| Spec score · Network Testing Software | 8.1 (#10) | 6.8 (#29) |
| Purpose | iperf3 measures achievable bandwidth on IP networks and reports throughput, loss, and other test results. | Shadow is a scientific experimentation tool for research, development, testing, and evaluation of real networked applications on simulated networks. |
| Support | The project provides a developer mailing list and GitHub issue tracker for questions and bug reports. | The project directs users to GitHub Discussions for community support and GitHub Issues for bug reports. |
Plans
In their own words
iperf3
iperf3 is a free command-line network measurement tool that reports achievable IP-network bandwidth, throughput, loss, and related results. It includes client and server functions for TCP, UDP, and SCTP tests, with adjustable timing, protocol, and buffer settings. Client or server output can be emitted as JSON, including line-delimited JSON for real-time parsing, and a library version can be embedded in other programs. The project uses a three-clause BSD license and lists Ubuntu Linux, FreeBSD, and macOS as its officially supported platforms. Windows is not officially supported; its FAQ points users with Windows problems toward iperf2. ESnet supplies source distributions rather than binary packages and recommends checking SHA256 checksums. iperf3 began as a perfSONAR bandwidth tester, its primary user base. It is not backwards compatible with the original iperf. Version 3.22 was released September 29, 2026.