GNS3 vs Netperf

GNS3 is free, open-source software for emulating, configuring, testing, and troubleshooting virtual and real networks. Its graphical client works with a virtual machine, and servers can run locally or remotely. Users can combine emulated devices running actual images with simulated devices, including a built-in layer 2 switch. It supports appliances from vendors such as Cisco, Brocade, Cumulus Linux, and HPE, as well as Docker, QEMU-based appliances, VMware, VirtualBox, Hyper-V, and connections to real networks. The GNS3 Marketplace offers preconfigured appliance templates with recommended settings. It runs on Windows, macOS, and Linux; documentation recommends the GNS3 VM for most Windows and macOS setups and complex topologies. Users must supply their own Cisco IOS images. There are no monthly or yearly license fees, and device capacity depends in practice on the host computer’s CPU and memory. GNS3 is used for networking education, certification practice, proofs of concept, demonstrations, and interoperability testing. A server has no authentication enabled by default and should be restricted at the network level.

Netperf is an open-source, self-hosted utility for measuring network performance. It reports unidirectional throughput and end-to-end latency through a client-server arrangement: netperf runs tests and netserver supplies the server side. Netserver can run as an inetd child or standalone daemon. The manual describes TCP and UDP transfer and request/response tests over IPv4 and IPv6 sockets, plus XTI, DLPI, Unix domain socket, and SCTP tests. Where the platform and build support it, results can include CPU utilization and service demand. Optional configuration enables STREAM pacing, timing histograms, and interim results. The primary distribution is source code, intended for systems without readily available binaries. Reported Windows builds use Cygwin, the Windows DDK, or Microsoft Visual Studio 2003; the README discusses an OSX naming workaround. Hewlett Packard Enterprise released this version under the MIT license. The project warns that its manual may be outdated, and several test families require explicit configuration.