Among the many dilemmas facing operators as they move towards the new software-based 5G architectures is one of timing. They can deploy relatively mature virtualized cores right now, if they rely on virtual machines and the NFV (network functions virtualization) platform that has been the bedrock of telcos’ cloud migrations so far.
But this approach is increasingly seen as a compromise – far more complex, heavy and cumbersome than the emerging cloud-native platforms. These rely on lighter containers and agile orchestration frameworks, which can configure, reconfigure, assemble and reassemble microservices on the fly, and in limitless combinations, to meet a particular user requirement.
However, if an operator is in a hurry, cloud-native platforms remain immature and there are question marks over how robust and telco-grade they are at this stage. No operator will risk the quality of experience of its users with untried technology in the core, but the MNOs also do not want to deploy in haste and be left with out-of-date technology that puts them at a disadvantage in terms of flexibility to support many kinds of use case. The risk for the vendors is that most MNOs ‘wait and see’ – first in the core, and then in the RAN, where even NFV-based solutions are still seen as high risk at this point.
However, vendors, the cloud industry and other players are working to accelerate the readiness of fully telco-grade cloud-native offerings, and setting out a clear roadmap to a world beyond NFV. This was symbolized in last week’s decision by the year-old Common NFVi Telco Taskforce (CNTT) to change its name to the Cloud iNfrastructure Telco Taskforce. This is designed to reduce the emphasis on NFV and embrace the emerging solutions too.
The CNTT was formed last July as a partnership between the MNO trade association, the GSMA, and the Linux Foundation (LF), which hosts many open source telecoms network initiatives. Although NFV itself was defined by standards body ETSI, many projects that have grown up around NFV, such as the Open Platform for NFV – which focuses on pragmatic deployability issues such as efficient testing – are under the auspices of LF.
The aim of the CNTT is to ease the transition to NFV, and then to containers, for operators. Its founding mission statement was to “work closely with global service providers to define and create VNF reference architectures for NFVi (consisting of a global NFVi reference model, reference architecture, and global VNF certification lifecycle). The common NFVi reference architectures will be submitted to LFN for testing and verification via the OPNFV Verification Program (OVP).”
The decision to make the subtle but important name change was taken “to better reflect what role the group plays in the open source community and more closely tie the name to our actual objectives,” an LF spokesperson said. “We are focused on establishing reference models and architectures for infrastructure to support cloud-based applications, in whatever form they take.”
According to the Linux Foundation’s Arpit Joshipura, general manager of networking, edge and IoT, the 5G network is a hybrid where VMs will reside with containerized network functions (CNFs) for many years. “Containers and VMs have to work together,” he said.
Vendors agree. Speaking in the recent virtual Red Hat summit, Marisa Viveros, VP of strategy for telecommunications, media and entertainment at IBM, said: “I think that telcos are going to run networks in the future that use both VMs and containers. They can’t decommission what they already have because it will be too expensive. Some will continue to run the physical network, the virtualized network and the containerized network. They can mix and match depending upon the topology and geographic locations.”
The CNTT has just released its latest release of specifications, codenamed Baldy, which includes its first container-based reference architecture, RA-2. This follows its first reference architecture, unveiled last autumn, which is based on traditional OpenStack VM technology, while its successor supports the Kubernetes container framework.
The new-look CNTT – whose operator members include AT&T, China Mobile, Orange, Verizon, Vodafone, STC and Telstra – now has three workstreams – OpenStack, Kubernetes containers, and telco edge architectures.
At the start of this year, more than 80 organizations worked together to develop the world’s first 5G cloud-native proof of concept (PoC), under the auspices of LF. The prominent role of operators showed how the telecoms industry is seeking to leverage its 5G advantages, combined with its own shift to open source and the cloud, to challenge the webscale players in key emerging opportunities such as edge compute.
The 80 organizations included telcos, developers, vendors and other LF members, which between them built all the elements of the live PoC. The Foundation was quick to contrast the speed with which this was created through cooperative, open processes, with the slow-motion pace of the traditional telecoms industry.
At the time, LF gave three pieces of advice to operators which want to thrive on the combination of cloud-native and 5G technologies. These are:
- Don’t use containers as yet another proxy for traditional telco devices
- Embrace more application-oriented cloud network design principles
- Fully use the CI/CD (continuous integration and continuous delivery) approach to application design and deployment.