Open Source Software: Cumulus Linux vs Big Switch vs Pica8

Open source software is the software that can be purchased separately for being installed on bare-metal devices. It is an essential part of today’s open networking. Combined with the bare metal switch, open source software create an open installation environment for IT staff to build a network with choices, better tools and cost improvements. Here, we’ll focus on open source software, and introduce several popular software on the market, including Cumulus Linux, Big Switch and Pica8.

cumulus linux network

What Is Open Source Software?

Open source software is also known as Network Operating System (NOS), which can be installed on a bare metal device such as a Gigabit Ethernet switch to make the devices “do things”, such as develop software, run applications and more.

In the past, a network switch is usually purchased as “black boxes” where the hardware and the software are tightly coupled together. In this way, customers can not get one without the other. For example, if one customer buys a Cisco Catalyst 4948 10Gb Ethernet switch, he will get the physical switch (hardware) and IOS (software) both.

In contrast, today, with the open networking develops, the hardware and software are decoupled. This means the same open source software can be run on multiple hardware configurations, or the same hardware can support different OSes. But notice that, choosing a NOS should depend on some factors such as hard compatibility (e.g. Cumulus have a partnership with Dell, HPE, etc.), supported features and level of support available.

What Are the Benefits of Open Source Software?

Open source software brings some benefits, including:

  • Power of choice. As mentioned above, IT staff can choose a NOS that suits their own hardware freely, avoiding vendor lock-in. Besides, selecting a NOS that they are familiar with, IT persons don’t need to spend extra time learning a new OS. So they can quickly control the software, and improve working efficiency.
  • Long term use. Since open source software is in the public domain, and OS suppliers such as Cumulus Network will constantly update their OS versions. So the suppliers will always keep checking the bugs and improving the performance of OSes, there is little chance that open source software may become unavailable or quickly outmoded. Thus, choosing open source software is an important plus for long term projects.
  • Cost saving. Generally, bare-metal switch are less expensive than the standard switches. For example, a 10Gb 48 port bare-metal switch from FS.COM costs 2999 dollars, while a standard 10Gb Ethernet switch with 48 ports needs 3599 dollars. Besides, the operating expenses are also less than from the proprietary vendors. Thus, the CapEX and OpEX can be reduced.

Software On the Market: Cumulus Linux vs Big Switch vs Pica8

According to the wide use of bare-metal switches, there is also a growing demand for open source operating systems. More and more companies start to develop OSes, such as Cumulus Networks, Big Switch Networks and Pica8. The following are the OSes produced by these suppliers.

Cumulus Linux

Cumulus Linux is a Debian based Linux distribution, which can be installed on a variety of commodity hardware such as Dell, Delta bare metal switch. Cumulus Linux allows users to take advantage of the existing automation tools for automatic configurations, which increases network stability and uptime. Besides, Cumulus Linux adopts web-scale methodology with network automation, helping customers to reduce costs by automating their networks.

Switch Light

Switch Light OS is a complete SDN operating system based on Open Network Linux (ONL), which is closely integrated with white box switches. This can ensure OpenFlow-like features to run on the current generation of switching chips for the data centers. Big Switch uses Big Cloud Fabric and Big Monitoring Fabric to address real business cases. Big Cloud Fabric enables virtual private cloud based logical networking, providing network automation and visibility for enterprise clouds and multiple public clouds, and Big Monitoring Fabric can offer end-to-end visibility and security for applications based on the network behavior.


PicOS supports two versions, PicOS enterprise edition and PicOS SDN edition. Both the two versions contain the same Debian Linux distribution with the same unmodified kernels, which can achieve the maximum programmability of DevOps. Pica8 sells PicOS separately that can run on bare metal switches from some vendors like Inventec, Edgecore Networks, or its OS could be sold with their own white box switches. Note that the enterprise edition support CrossFlow, which is the ability to run both L2/3 and “classic” SDN OpenFlow control planes on every switch port in a network at the same time via CrossFlow. This is the biggest characteristic PicOS.

These OSes can be installed on the compatible bare-metal switches, customers can choose one according to the specific demands.


Open source software from Cumulus Linux, Pica8 and Big Switch Networks are attractive to customers. These OSes bring many benefits like cost saving, long term use and flexibility of hardware and software choices, avoiding vendor lock-in. But remember to check the compatible hardware lists before buying one.