Key Insights into the Open Network Switch & Open Network Operating System (ONOS)

Updated on Jan 23, 2024 by

What Is Open Network Switch?

Unlike traditional switches, open network switches feature hardware and software components supplied by distinct entities. This enables independent modifications without mutual interference. Simply put, the hardware of an open network switch is flexible, supporting multiple operating systems from various vendors and capable of running on different hardware configurations.

It is important to note that an open network switch is not the same as an open source switch. Open source refers to software or programs that are accessible to the public for use and modification. On the other hand, open networking focuses on software specifically crafted to enhance the flexibility, compatibility, and automation of network devices.

In recent years, open network switches have already become the first choice of cloud providers for their high performance, simplicity, free choice for users, fast innovation, low cost and etc.

However, open network switches cannot work effectively without software. That's why the operating system is so important to them.

So, what is an open network switch operating system? Which companies commonly have the reputation of being open network switch vendors? Keep reading to know more details.

Open Network Switch

What Is Open Network Switch Operating System?

To understand what the open network switch operating system is, it is necessary to look at its predecessor, the network operating system (NOS).

Network Operating System (NOS)

A network operating system (NOS) is a computer system that controls network resources. It also connects devices to a local area network (LAN). Generally, NOS can manage several input requests at the same time while enabling security in a multi-user environment. NOS has four modules: infrastructure, management interface, hardware interface, and protocol application module.

Open Network Operating System (ONOS)

ONOS is deployed and run on switch devices as a network operating system. Specifically, it serves as an open source, distributed software-defined network (SDN) controller. ONOS achieves network flexibility and programmability by communicating with switches to guide and manage the flow of network traffic. This centralized control plane is one of the core ideas of the SDN architecture, making it easier for the network to adapt to different application requirements and changing network conditions.

Working Principles of ONOS

ONOS (Open Network Operating System) works based on the concept of software-defined networking (SDN). By separating the control plane and the data plane of the network, it can realize flexible and programmable network control. Here are the main aspects of how ONOS works:

  • Distributed Core: ONOS uses a distributed architecture. Multiple nodes collaborate to form a unified control plane. The design supports large-scale networks with high scalability and performance.

  • Southbound API: ONOS communicates with network devices such as switches and routers through a southbound interface, allowing ONOS to retrieve information about network devices and issue control commands. It can also manage multiple devices with different protocols. This is done by using extensions in a pluggable form. In addition, the southbound API can easily realize the transfer from legacy devices to OpenFlow devices.

  • Northbound API: ONOS provides services to upper-layer applications through a Northbound Interface. These applications can include network management, monitoring, security, and various other network services. This function separates network operating systems from applications, allowing network changes without application downtime.

  • Software Modularization: As a main feature of the ONOS, software modularization enables the community developers and providers to easily develop, debug, maintain, and upgrade the ONOS. It maintains ONOS architecture integrity and reduces negative impact of system changes, making maintenance easier.

    ONOS Architecture

Development and Evolution of ONOS

To be clear, ONOS architecture is not that complete at the very beginning. In fact, it has undergone two major evolutions.

  • Stage Ⅰ: In the beginning, equipment vendors like Juniper and Arista have control over core technologies, making them strong competitors. Currently, NOS infrastructure is basic and the management interface and protocol application module are merged. Later, JunOS OS for Dummies introduced modular architecture, separating management interfaces from other modules.

  • Stage Ⅱ: With the development of Software-defined Networking (SDN), a new generation of open and independent network operating system has emerged. These emerging ONOSs are based on database architectures. However, relying on database architecture alone cannot meet the needs of enterprise for faster and more flexible connections. Therefore, many cloud providers choose to integrate database architecture with containerized architecture. The chart below clearly demonstrates how network operating systems have developed and evolved.evolution of ONOS

Due to the low cost and simplicity of open network switch operating system, more and more hyperscale cloud providers have adopted this system in their data centers. With ONOS, IT staff can solve network issues easily, even without extensive knowledge of the underlying network. More cloud providers also offer rich technical support services, which increase the enterprises' requirements for ONOS.


Open Network Switch Vendors

As mentioned above, more and more large enterprises and cloud providers are opting for open network switches for data centers today. Below is a brief description of the major white box vendors in the market.

Hardware vendors

The providers of open source network switch hardware mainly include Dell, Accton, Celestica, EdgeCore, Quanta, Foxconn, Asterfusion, FS, etc. All of them use the same Broadcom chipsets.

  • FS: A company in the field of network communications, also offers open network switches. In order to guarantee the proper operation of its hardware compatible with open source software, FS has pre-installed the PicOS® series of devices. At present, FS has developed deep cooperation with Pica8.

  • Dell: As a large network enterprise, Dell provided some of its products as open switches. Besides, it also supports NOSs from cloud vendors, such as Big Switch and Cumulus.

  • Asterfusion: Asterfusion is a supplier of open network switches. They offer open network solutions and their own SONiC enterprise distribution for data centers and service providers of the future.

  • EdgeCore: EdgeCore Network is one of the major open network switch hardware vendors. To make sure that open-source software runs properly on its hardware, this company is strengthening the partnership with the Open Networking Foundation (ONF).

    Open network switch

Software vendors

The main suppliers of open network software include Big Switch, Pica8, IP Infusion, Arrcus, Pluribus, Kaloom, Cumulus and Snaproute.


Pica8 is a leading innovator in the development of open network systems, specializing in software-defined networking (SDN) open systems and open network switches.The Pica8 family of products includes the PicOS® family, PicOS-V, and the AmpCon™ network manager.

  • PicOS® is an open network operating system developed by Pica8. The main function of PicOS® is to transform a white box switch into a fully functional switch while automating it through the AmpCon™ network manager. PicOS® also provides a virtual machine (VM) version called PicOS-V so that users can become familiar with the PicOS® software switch.

  • AmpCon™ is a network controller used to automate zero-touch provisioning (ZTP), deployment, configuration, and lifecycle management of PicOS® software switches.PicOS-V is a free virtual machine (VM) provided by Pica8 to help familiarize yourself with PicOS® software switches.

In addition, Pica8 offers a single license model, which means one license per device to use all features anywhere on the network.Pica8 also offers open network switches that can be configured through traditional CLIs and modern automation tools.

Other software vendors

Other software vendors, such as Big Switch, offer Switch Light NOS. this NOS does not interact with the operator, but rather proxies applications running on the SDN controller.

IP Infusion is a company that provides network operating systems (NOS) and software solutions. IP Infusion's products include OcNOS™ ( Open Compute Network Operating System), ZebOS® Network Operating System, and other software suites. IP Infusion's solutions are designed to help customers build, manage, and optimize their network infrastructures to meet the evolving needs of communications and cloud computing.

open network switch

FS and Pica8

The collaboration between FS and Pica8 is committed to enhancing future partnerships, understanding customer needs thoroughly, and advancing the growth of open networks. This entails providing dependable, flexible, efficient, and scalable software and hardware solutions to customers in the enterprise, SMB, data center, and ISP sectors.

FS.com is now licensed to sell the complete range of Pica8 products, offering bare metal and PicOS® software and hardware integrated open network switches. The PicOS® product line, AmpCon™ network controllers and comprehensive support services can be accessed through FS. Meanwhile, it offers PicOS®-compatible open network switches, and will be continuously updating with more adapted hardware and related services in the future.

Do you want to experience a better network operating system? FS offers a range of solutions for your organization. Experience PicOS-V online or sign up for a free trial.


In conclusion, with the development of NOS, open network switches can achieve much better performance at a relatively low price, which can bring many benefits for cloud providers. Therefore, more and more cloud vendors are moving from traditional switches to open network switches to better meet the needs of enterprises and data centers.

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