IMUNES

IMUNES is a network emulation and simulation environment for building general-purpose IP experiments. It is best suited to network engineers, researchers and educators who need configurable nodes and links; its Linux privilege and Docker requirements make it a poor fit for restricted hosts.

Its combination of detailed node configuration and real-time emulation makes it a strong no-cost lab tool, provided your host can run it.

Overview

IMUNES brings topology management, node setup and network emulation together in a GUI. The project says hundreds to thousands of virtual nodes can run on one physical machine, with experiments instantiated in seconds and efficient use of hardware resources. That is an attractive way to build sizeable labs without dedicating a separate physical device to every node, though actual capacity still depends on the host.

Each virtual node has its own IPv4 and IPv6 configuration, IPsec, sockets, firewall settings and address space. Preserving standard UNIX APIs lets BSD and Linux binaries run unmodified, which helps when experiments need to represent conventional systems rather than an abstract network model.

Key features

Topology and traffic control

The GUI supports management, automated node and link creation, and configuration. Links can impose delay, bit-error rate, duplication and bandwidth limits, giving users control over conditions that can be difficult to reproduce consistently with physical equipment. This depth favors users who need to shape experiments precisely; it is less compelling for someone seeking only a simplified network diagram.

Live operation and automation

JSON configuration and live mode support changing nodes, interfaces and links while an experiment is running. Alongside an automation API, these capabilities suit repeatable experiments and evolving scenarios without requiring every change to be made before launch.

Emulation model

IMUNES supports real-time emulation and hardware-in-the-loop, making it relevant to experiments that need to interact with real equipment as well as virtual nodes. It is an emulation-based tool, so users seeking a different simulation model should compare alternatives before committing.

Pricing

IMUNES is open source and free: the plan costs nothing. There are no paid tiers to choose between, so its node and link controls do not depend on upgrading to unlock a more capable plan. The trade-off is operational rather than financial: Linux experiments require the Docker daemon and must be run as root, which may rule it out on managed or security-restricted systems.

The project provides public source repositories, examples, security examples, manuals and virtual-machine images. Its latest listed image is IMUNES-FreeBSD-14.3-RELEASE (BETA), a 4GB amd64 OVA. The beta designation matters for anyone choosing that prebuilt route; the project also provides source and documentation for users setting up their own environment.

Platforms

IMUNES runs on FreeBSD and Linux, with different mechanisms on each: FreeBSD uses jails and netgraph, while Linux uses Docker for virtual nodes. Linux requires kernel 3.10 or later, a running Docker daemon and root privileges for experiments. Those are meaningful prerequisites, not incidental setup details, and make FreeBSD the more direct choice for users who do not want Docker in the execution path.

The directory categorizes IMUNES across Linux, macOS, self-hosted, web and Windows platforms, but the project describes the emulator itself as running on FreeBSD and Linux. The practical host requirements above should guide platform selection.

Who it's for

IMUNES is a strong fit for network engineers, researchers and educators who need configurable IP topologies, traffic manipulation and support for standard BSD or Linux binaries. Its use in Ericsson Nikola Tesla product testing and University of Zagreb teaching laboratories illustrates both product-testing and instructional contexts. The ability to run large virtual labs on one machine is especially useful where physical equipment would be cumbersome.

It is less suitable for users without administrative access, or for those who cannot provide Docker on Linux. Readers who need a turnkey tool on a restricted workstation should favor an option compatible with their host and access policy instead.

Pros and cons

Pros

Fine-grained node and link controls: independent node configurations plus delay, error, duplication and bandwidth controls support realistic, repeatable IP experiments.

Large labs on one host: the project targets hundreds to thousands of virtual nodes, reducing the need to assemble a physical device for every topology element.

Unmodified UNIX binaries: preserved standard APIs let BSD and Linux programs run without modification inside experiments.

No-cost, open-source access: source repositories, manuals, examples and security scenarios are available without a paid plan.

Cons

Linux requires elevated access and Docker: root execution and a Docker daemon can conflict with managed-host policies.

Linux has a kernel floor: kernel 3.10 is the minimum, which may exclude older or constrained installations.

The prebuilt FreeBSD image is beta: users relying on the listed 4GB OVA should account for its beta status.

Alternatives

Compare network simulation software if you want to weigh emulation tools against other approaches.

OMNeT++ is worth considering for noncommercial teaching or research, with a free academic license and a free trial; its listed platforms include Linux, macOS, self-hosted and Windows.

EVE-NG may suit users who want a freemium alternative across Linux, macOS, self-hosted, web and Windows. Its free tier is limited to 7 nodes per instance, 63 per lab and the Admin role; the Base plan is priced on request and remains Admin-only.

Cisco Modeling Labs is a better fit when Cisco nodes are the focus: CML-Free allows 5 running nodes, while Personal supports 20 Cisco nodes for one user and Personal Plus supports 40 Cisco nodes for one user.

GNS3 is another free open-source option for users comparing network emulators.

Kathará is a free open-source alternative with API support and no stated usage limits.

Mininet may suit Linux users seeking a permissively licensed option, but it is limited by one server’s CPU and bandwidth.

ns-3 is a free GPLv2 tool for research, development and use if that project’s approach better fits your work.

OMNEST is an option for users considering commercial licensing, with annual licenses priced by quotation.

Verdict

Choose IMUNES if you need detailed IP node and link controls, real-time emulation and the freedom to run experiments at no charge. Its strongest reason to look elsewhere is also clear: Linux use requires Docker and root access, so users without that control should choose a tool compatible with their host and security constraints.