At Open Infrastructure Summit in Denver, it became clear that, as 5G rolls out, it's going to be running on Kubernetes. Telecoms have been fiddling with Kubernetes, the leading container-orchestration system, for some time now. AT&T recently stopped tinkering with Kubernetes and invested eight figures in a multi-year deal with Mirantis to use Kubernetes and OpenStack as the foundation for its 5G rollout.
That's serious bucks -- even for AT&T. So, why do it?
At the time, Ryan Van Wyk, AT&T associate VP of network cloud software engineering, said: "There really isn't much of an alternative. Your alternative is VMware. We've done the assessments, and VMware doesn't check boxes we need."
What are these boxes? For AT&T, they're Virtual Network Functions (VNFs) -- such as vEPC (Virtualized Evolved Packet Core), RAN (Radio Access Network) backhaul, traffic shaping services, customer usage tracking, smart voicemail, video streaming, and consumer facing services. In short, everything and the kitchen sink.
Behind the jargon, AT&T is changing its game from using big boxes from incumbent hardware providers into building its own infrastructure based on open-source software and standards.
AT&T isn't relying on open-source vendors for its future 5G infrastructure. AT&T is working with Intel, Mirantis, and SK Telecom on Airship, a hybrid combination of the OpenStack cloud and Kubernetes.
"Airship allows cloud operators to manage sites from their creation, to minor updates, through configuration changes, and finally major uplifts such as OpenStack upgrades, via a unified, declarative, fully containerized, cloud native platform," said Van Wyck.
There are other approaches. Arpit Joshipura, The Linux Foundation's general manager of Networking, Edge, and IoT, believes this hybrid model -- where VNFs live in OpenStack-based VMs packaged for Kubernetes -- is an evolutionary step.
"We're looking at moving from that hybrid model to where you write CNFs with cloud native in mind, and then putting them on Kubernetes side-by-side with bare-metal and OpenStack," said Joshipura.
In practice, Verizon already has about 80 applications in production or near-production on Kubernetes managed containers. Nanda Kumar, a Verizon systems engineer, said at KubeCon North America 2018 that most of these are stateless, but they're "expanding into more robust stateful applications." For Verizon, the drivers for its Kubernetes move are cost saving and "fast tracking our transformation."
"[Kubernetes are] a less 'resource intensive' alternative to virtual machines (VM)s. it enables the utilization of best features of container-based solutions -- such as quick deployment, easiness to make changes, and much lighter 'cost of ownership' impact on the resources with best features previously seen on 'bare metal' deployments. This results in lightweight, highly-available, and secure deployments, which can be done, if prepared properly, in consistent and automated way independent of actual service being rendered."
Jacob Smith, co-founder of Packet, a leading infrastructure automation company, believes "the massive infrastructure investments being made by existing and 'new' telecom providers rolling out 5G and CBRS wireless" is driving the move to Kubernetes. "With hundreds or thousands of locations needed to drive low-latency and cost-effective operations, the appeal of highly deployable and portable Kubernetes-based infrastructure is hard to resist," he explained.
Looking ahead, Kubernetes will continue to drive 5G's engine.
As Joel Lindholm, vice president for business development for Ruckus Networks, said: "Kubernetes will continue to be an important technology/enabler for LTE/5G networks and critical applications that enterprises run on these networks. We believe simplicity and automation are critical to pervasive use of cellular networks."