iPerf2 vs TRex

iPerf2 measures network traffic performance, including throughput, latency, link capacity, and responsiveness. Testing uses a client to send traffic to a server. It can generate TCP and UDP traffic in one-way, bidirectional, full-duplex, and simultaneous multi-stream configurations. Measurements include one-way delay, round-trip time, jitter, packet loss, and throughput. It supports IPv4, IPv6, and multicast, including source-specific multicast joins, and reports can include enhanced metrics or use CSV format. The project manual describes an Android client with live meters for throughput, latency, and congestion signals. The manual also describes permit-key HMAC authentication using a timestamped HMAC-SHA256 value, with replay limited by a configurable time window. Its Professional feature set includes server access gating and remotely enabled server-side latency histograms. Measurements happen at socket-level reads and writes, so lower-level protocol-header overhead is excluded. iPerf2 and iPerf3 are separate implementations and do not interoperate. It runs on Android, Linux, macOS, and Windows, and can be self-hosted. Both listed editions are free.

TRex is an open source traffic generator for benchmarking platforms with realistic network traffic. It produces Layer 3–7 traffic in stateless, stateful, and advanced stateful modes. Stateless mode supports multiple streams, packet-field changes, and per-stream or per-group statistics, latency, and jitter. Advanced stateful mode emulates Layer 7 traffic over scalable TCP and UDP flows. Emulation includes ARP, IPv6, ND, MLD, IGMP, ICMP, DOT1X, DHCPv4, DHCPv6, and DNS. TRex offers Python automation APIs and a console interface; stateless functions can also be used through JSON-RPC. The manual describes it as a Linux application using DPDK and Linux kernel modules, intended for COTS x86 servers. The site says one server can scale up to 200 Gb/sec. It can run in a virtual machine or Docker for low-performance, low-footprint use, but virtual switches can limit throughput and virtual-machine latency results are not accurate. TRex is free, with hardware and NIC requirements. The GUI monitoring application TRexViewer is supported only on Windows.