GNS3 vs TRex
GNS3
gns3.comTRex
trex-tgn.cisco.comSide by side
| Figure | GNS3 | TRex |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| API | — | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 1 | 1 |
| Spec score · Network Testing Software | 8.1 (#9) | 7.9 (#15) |
| Purpose | GNS3 lets network engineers emulate, configure, test, and troubleshoot virtual and real networks. | TRex is an open source traffic generator for benchmarking and testing network devices with realistic traffic. |
| Security | GNS3 documentation says a GNS3 server has no authentication enabled by default and should be restricted at the network level. | The opened official pages do not state security certifications or compliance claims. |
| Support | GNS3 points users to its documentation and community for help, questions, and bug reports. | The documentation lists a TRex community forum and Cisco DevNet community as support resources. |
Plans
In their own words
GNS3
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.
TRex
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.