What Are Open Network Operating Systems?

Disaggregated networking first became prevalent in large data centers. Hugely scalable chipsets in white box hardware enabled open networking and the separation of hardware and software in telecom networks. Cloud-based gaming, augmented reality, virtual reality, and the IoT are accelerating the adoption of disaggregated networking solutions.

Originating in Large Data Centers

The concept of open (or disaggregated) networking was introduced by hyperscale data center providers, such as Google and Amazon. The underlying concept was to separate the hardware layer from the software (open network operating systems, NOS), which in turn fostered a newfound ability to customize networks according to one’s needs.

While open networking started with  hyperscale data centers, it gained traction in telecom service provider networks starting in 2016, thanks to the release of a new generation of chipsets, such as the Broadcom DNX family. This was a critical advancement in open networking as the new chipsets supported the large scale routing capabilities required in telecom networks.

Transition from Vertically Integrated Routers to Fully Disaggregated Routers

Open network operating systems

Large Scale Routing Hardware for Telecom Networks

The introduction of Broadcom DNX ASICs enabled manufacturers to create scalable IP routing hardware from off-the-shelf equipment with capabilities from a few Tbps up to 1,300 Tbps, suitable for use in Tier 1 Communication Service Provider (CSP) networks.

As a result, hardware manufacturers designed and released complete portfolios of white box hardware designed for all the network applications found in fixed and mobile service provider environments.

The new chipsets opened a world of new applications such as internet peering, where millions of IP routes are stored in high-speed memory to apply instant routing decisions. Additionally, the new generation of chipsets enabled features such as hardware-based Quality of Service (QoS), programmable packet processors for MPLS, L2 VPN, and L3 VPN.

Disaggregated Routing Software

In addition to networking hardware, disaggregated routing solutions require open network operating systems to take full advantage of the processing power of the underlying hardware.

A carrier-grade router needs to have several key attributes:

  • High reliability and serviceability
  • Quality of Service (QoS)
  • Quality of Experience (QoE)
  • High performance and efficiency
  • Scalability
  • Security

At the kernel, an intelligent operating system with a rich set of algorithms ensures that all these attributes are addressed accordingly, in a balanced and dynamic manner.



ExaNOS is routing software from Exaware that addresses the needs of nearly any use case in applications for access, aggregation, edge/PE, and network peering. The distributed architecture enables massive scale routing with a wealth of features including traffic forwarding decisions, filtering, and all other features needed in a carrier-grade internet router.

Acting as the brain in Exaware’s disaggregated IP/MPLS routing solutions, ExaNOS is the vital piece of the open networking puzzle for CSPs of any size.

ExaNOS runs on any Broadcom DNX-based chipset white box architecture and opens the gates of network innovation and flexibility by enabling a growing roster of 3rd-party network applications to seamlessly plug in. This versatile capability enables carrier-grade operators to hyper-scale continuously and innovate with ease to meet the growing needs of their customers.

Open network operating systems

Open Networking Solutions Put Power in the Hands of Users

At the macro level, the main idea behind open networking is to bring back power to the users and provide them with freedom of choice, while dramatically reducing networking costs both in the short- and long-term.

Open networking moves away from the traditional, highly rigid proprietary driven model, standardizes the network hardware, and separates hardware from software to provide flexibility and agility to meet the changing needs of business.

Traditional Closed Rigid Models

Over the last several decades, industry-leading networking giants such as Cisco Systems and Juniper Networks delivered their hardware with proprietary operating systems, tightly coupled together, such as Cisco IOS and JUNOS, respectively. These closed solutions require proprietary operating system software to work exclusively with their hardware, without other vendor options.

In a traditional network, hardware and software is aggregated, or linked. This presents limitations that result in much higher capital expenditures and operational costs, as well as throttling flexibility and innovation in network design. A CSP using aggregated products is limited to the current state product design offered by the vendor. Even if updates occur periodically, they may not meet the CSP’s current needs. Basically, the customer is locked into the proprietary solution.

As network functions such as cybersecurity become more granular, the open disaggregated model will continue to gain adoption.

Components in an Aggregated Networking Model

In the traditional model, the following components make up an aggregated single product:

  • Hardware
  • Software
  • Silicon
  • Architectural design

Gain Flexibility in Network Design with Disaggregated Networking

The advent of disaggregated networking is an industry game-changer, in the same way open source software was. CSPs have more vendor options, which can more closely meet their business needs without paying for unneeded out-of-the-box features offered in the traditional closed networking model. Network operators can deploy new solutions without being tied to an incumbent vendor.

5G, Cloud Technologies, and the Disaggregated Network

The transition to 5G is likely to accelerate the adoption of open networking solutions, with higher demand for cloud-based gaming and Web 3.0 metaverse related platforms using 3D/AR/VR, as well as the increased growth of the Internet of Things (IoT) and Smart Cities. These applications can be enabled by mobile networks only if mobile network operators can build a sustainable business model where revenues exceed network costs.

The need for software for open networking in the cloud is rising, with mission-critical applications increasing demand and capacity needs. Open networking will expand the communication between cloud-based applications and networks, for the greater benefit of end users. Additionally, open network operating systems will further decrease cloud computing costs and offer a cost-effective solution to millions of businesses worldwide.

Decoupling Traffic Growth from Network Costs

For providers using only traditional routing solutions, traffic growth and network costs tend to rise in tandem. This has been particularly painful for mobile operators and 5G deployments.


Exaware gives you the ability to gradually scale your network, a single white box at a time, thanks to the ExaNOS distributed chassis architecture, which can grow linearly from a few Tbps to 1,300 Tbps.

To learn how you can reduce costs up to 50% and eliminate vendor lock-in, contact an open networking specialist today.

Contact a Specialist

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