Cloud-native network function group to define what 'cloud native' means in telecommunications

January 4 2021
by William Fellows


The Cloud Native Computing Foundation (CNCF) has established a cloud-native network function (CNF) working group to define what 'cloud native' means in telecommunications. It will provide an open source CNF test suite that will demonstrate the extent to which cloud-native best practices are implemented, for both open and closed source CNFs. CNCF hopes the outputs will increase interoperability and standardization of cloud-native workloads in the telco space to reduce what will be a significant operational burden on service providers as they re-platform to cloud-native services and service delivery.

The 451 Take

Our view is that in order to realize the 'interconnected world,' telecom operators will migrate virtualized network functions to containerized network functions, but this is a several-year journey. The ability to support virtualized functions and containerized functions (VNFs and CNFs) from a single management and orchestration platform is desirable, a significant opportunity for innovation. Cloud native brings the ability to rapidly and cost-effectively scale and continuously update features and functionality. It provides both the technology components and design process (DevOps). Together, they enable services to be assembled, connected, consumed and reused. In the meantime, telcos are also looking to cloud, 5G and edge to restore their image on Wall Street (and therefore shareholder value) in a climate where the network has been regarded by the investment sector as essentially dumb pipes, with their owners unable to monetize the data moving over it (having lost out to the OTT operators in 3G and 4G). However, the pandemic has demonstrated the operation and importance of networks as critical infrastructure plus the robustness of their facilities. As these two forces intersect, telcos will be the outstanding buildout market opportunity for cloud native. The question is whether telcos, while being well-positioned with facilities, can also become the service providers on top.


The CNF Working Group sees itself as providing the upstream definition of what makes a telco application cloud native, allowing downstream projects to create precise programs and/or implementations for their specific needs. It will be utilized in Linux Foundation networking projects Anuket (CNTT2.0/OVP2.0) and ONAP, as well as other projects as needed. The test suite will be informed by existing Kubernetes e2e tests and Project Sonobuoy (diagnostic tool) and will support the ability to test multiple layers of the system, focusing on tests for certifying conformant cloud-native network functions. Kubernetes certification is determined by API conformance – CNF is working at the application layer where conformance will be determined by many things, including best practices. The CNCF expects the CNF Working Group will be formalized under a Special Interest Group within six months and to submit a CNF test suite as a sandbox project. The CNF Working Group will live alongside the CNCF's Telecom User Group.


The interconnected world is happening and will be driven by 5G (or subsequent iterations), edge and IoT. 5G sceptics are a dwindling band, and 5G is set to be a standout market buildout opportunity. For some, the replacement of Wi-Fi by enterprise 5G, globally, will result. However, it requires a technical change to applications, which CNCF believes it can address via the CNF Working Group. Its view is that the migration of physical network functions to virtual network functions was little more than lift and shift. This it sees as the 'cloud washing' of network functions that are merely virtual machines put into containers. Moreover, looking back at the experience of OpenStack, modifications and tweaks of OpenStack and network functions (lots of different versions) led to little interoperability among vendors. In short, it believes the operational model simply ported from running physical hardware has led to few gains in VNF operational productivity.

By contrast, the conversions required for 5G and cloud native require a new set of investments. The CNCF's view is that loosely coupled immutable (cloud native) systems are inherently better at handling highly complex applications with strict SLAs and multiple dependent and interactive functions, which 5G, edge and IoT demand. Its survey of telcos found that 90% are using Kubernetes – and more than 50% are in production where network functions, IT type workloads, management, operations and telecom edge workloads are the key workloads. CNFs use Kubernetes (containers) and run on bare metal or on any cloud, but CNF architecture also embraces VNFs (on OpenStack, KubeVirt, Virtlet).