iperf3 vs Ostinato

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.

Ostinato generates and customizes network traffic, or replays PCAP files, to help validate throughput, QoS, multicast, routing, switching, protocol behavior, and network performance. Users can edit supported protocol headers, set frame sizes, and create custom headers with hexdumps or scripts. PCAP replay can preserve or alter packet timing, loop traffic, or reorder packets. Native protocols include Ethernet, VLAN, QinQ, IPv4/IPv6, UDP, stateless TCP, ICMP, ARP/NDP, IGMP/MLD, and GRE; other methods can support headers such as MPLS and VXLAN. Reports show transmit and receive statistics, per-stream packet loss, and latency and jitter measured with software timestamps. A Python API supports stream and scenario creation, run control, counter collection, and CI/CD integration. Ostinato lists GNS3, EVE-NG, Cisco CML, and Containerlab as supported lab environments, and says it works on AWS and Azure cloud VMs. It runs on Linux, macOS, Windows, and self-hosted or API setups. Plans start at $12 a month billed annually; an active subscription is required.