ONOS

ONOS is a free, open-source control plane for software-defined networks, built for teams that need to manage network devices and run network services through software. Its distributed architecture and range of control interfaces make it a capable foundation for complex networks; Kubernetes-based deployment makes it a specialist choice.

Overview

ONOS provides abstractions between network applications and the devices they control. Applications can use north-facing interfaces, while south-facing interfaces support device management across protocols. This is a platform for building and operating network services, not a turnkey tool for routine administration of a small network.

Its symmetric cluster of identical instances distributes work and is designed to keep operating through instance failures. The µONOS architecture also describes high availability and dynamic scaling. Those properties suit networks where controller continuity matters, but operating its microservices calls for cloud or data-center infrastructure and Kubernetes.

Key features

• Network operations: µONOS supports device configuration, monitoring and maintenance, forwarding-plane programming, topology validation, and fine-grained performance metrics. That breadth helps operators manage and observe networks from the same control platform.
• Protocol and device interfaces: ONOS documentation names OpenFlow as its primary southbound protocol for programming switch flow tables, alongside OVSDB, NETCONF, and SNMP for configuration. µONOS also uses P4/P4Runtime, gNMI/OpenConfig, and gNOI, with gRPC connecting its modular microservices. The range supports varied control needs, though teams must choose and operate the interfaces appropriate to their network.
• External network connectivity: The SDN-IP application uses BGP to exchange traffic between an ONOS-controlled network and adjacent external networks, useful where an SDN domain must connect beyond its own devices.
• Web interface: The ONOS GUI is a cloud-native Kubernetes application built with Angular and gRPC Web to access backend modules. It fits the platform’s deployment approach rather than offering a separate, lightweight management option.
• Access control: Security Mode is intended to restrict applications’ access to northbound APIs, an important boundary in a platform that allows applications to interact with network control.

Pricing

ONOS is free: its ONOS plan costs nothing and is open-source software under the Apache License 2.0. There are no paid tiers or seat limits described. The trade-off is operational rather than a subscription cost: teams need the infrastructure and expertise to deploy and maintain the platform, including Kubernetes for µONOS microservices.

Platforms

ONOS supports API, Linux, macOS, self-hosted, and web environments. µONOS microservices are designed for cloud and data-center infrastructure using Kubernetes; Docker images and Helm charts are deployment options. Production deployments are directed to the release tar.gz package or Docker image, while development can use the source repository.

Who it's for

ONOS is aimed chiefly at service-provider networks, with data-center and campus networks also identified as possible uses. It is a stronger fit for operators building programmable network services across devices and protocols than for teams seeking a simple, ready-made network administration app. Its community-backed project points users to an FAQ, mailing list, and Slack team for questions.

Pros and cons

• Pro: A symmetric distributed design can spread work across instances and handle instance failures, valuable where a single controller would be a constraint.
• Pro: Support for multiple control and configuration interfaces gives network teams options across device types and operating needs.
• Pro: Apache 2.0 licensing and a free plan avoid software licensing fees and allow use of the published source code.
• Con: Kubernetes-oriented microservices require an infrastructure commitment that can outweigh the benefits for small or straightforward networks.
• Con: ONOS is a control-plane platform for building network services, not a general-purpose network management product; teams wanting routine administration may need a different category of tool.

Alternatives

OpenDaylight is another free, open-source SDN platform, available as a tar or zip download and as Docker images; consider it if that platform or packaging better matches your deployment plans.

.NET offers a free plan for up to 1,000 nodes and supports Windows, Mac, Linux, iOS, and Android; choose it if that node cap and broader platform coverage fit your needs better.

TP-Link Omada Cloud-Based Controller offers a lifetime-free plan with unlimited devices and sites and core management features; consider it for compatible Omada access points and managed switches.

Antrea requires a Kubernetes cluster and the Open vSwitch kernel module on every Kubernetes node; consider it if those requirements align with your environment.

Cilium is an open-source option for Linux with kernel version 5.10 or equivalent and AMD64 or AArch64 hardware; consider it if those platform requirements suit your deployment.

Kube-OVN is an open-source Kubernetes networking project under Apache 2.0; consider it if you are looking specifically for that kind of project.

Open Virtual Network is a free, open-source option under the Apache 2 license; consider it as an alternative if that project fits your needs.

VMware Workstation Pro is free for Windows or Linux hosts running on 64-bit Intel or AMD PCs, with no subscription or license key required.

Browse more options in Software-Defined Networking Software or Network Automation Software.

Verdict

Choose ONOS if you need an open-source control plane that can distribute network work and handle device control across a broad set of interfaces. Its main advantage is a flexible architecture for complex service-provider networks; look elsewhere if your needs are simpler or you cannot take on Kubernetes-based deployment and operations.