German telecommunication giant O2 Telefónica’s recent move to start porting live 5G traffic into a public cloud environment hosted by Amazon Web Services (AWS) and Nokia marks a significant step in the operative dance between the telecommunications and cloud space.

The deal itself will see the German telecommunications operator run a Nokia-sourced 5G Cloud Core platform on AWS’ public cloud infrastructure. This marks the first time a brownfield mobile telecommunication operator has migrated its existing network and customer base to a 5G cloud platform running on AWS.

O2 Telefónica started down that path late last year through a long-standing 5G core arrangement with Ericsson, which gained further momentum earlier this year with actual deployments.

Analysts have repeatedly stated that telecommunication operators need to more fully embrace these cloud architectures to maximize the performance of those networks and extract the most value from their network investments. However, public cloud resiliency remains an overhanging concern.

This was highlighted in late 2021 when AWS experienced a prolonged outage that impacted both basic applications and colossal businesses with hundreds of millions of customers.

ABI Research senior analyst Don Alusha at that time explained to SDxCentral that “communications service providers have much stricter service level agreements (SLA) and service-uptime guarantees remain stringent relative to cloud software and platforms. Operators stand to benefit from cloud innovation and agility, but they need to balance the risk of deploying cloud-driven methodologies and tool chains.”

These concerns have kept many operators from more fully embracing the public cloud model.

Adam Koeppe, SVP of network and technology planning at Verizon, told SDxCentral last year that while a cloud-native architecture allows for more dynamic network control, Verizon plans to maintain control over those network assets.

“Our goal from the start and still today has been we’re gonna have a network cloud that we run our core functions on; this is the network that faces the customers,” Koeppe said. “We are going to be responsible for that from beginning to end, the whole package. So placing those network functions on somebody else’s infrastructure, or cloud, is not even part of the equation.”

This mantra was echoed by rival AT&T executive Igal Elbaz, who told SDxCentral that “AT&T’s 5G mobility core runs on AT&T hardware in the AT&T data centers and operated by AT&T.”

However, both executives did note there was a place for public cloud to also be mixed into specific environments.

“We’ll probably see scenarios where a multicloud environment comes into the picture and pretty much almost always tied to an enterprise need,” Koeppe said. “If you’ve got an enterprise customer that is trying to manage some of their applications or workloads on a private network, on a public network, whatever the case might be, we can facilitate that type of architecture as well.”

AT&T’s Elbaz said these architectures also allow operators to better take advantage of tools and automation developed by hyperscalers.

“At the heart of this is how can we take advantage of the hyperscaler investment in tools, automation and cloud capabilities, because that’s their business and they are really good at it,” Elbaz said. “And knowing that this is how we are going to run the network going forward so why not take advantage of this.”

O2 Telefónica’s move to AWS shows operators are starting to lean more into that potential advantage.

“O2 Telefonica is very much testing the water with this exercise,” Elly Whittaker, reporter for ReThink Technology Research’s Wireless Watch, wrote in an email to questions, adding that the plan is to move 1 million customers onto the AWS/Nokia core this summer “and if things run smoothly, they will think about scaling up from there.”

Amir Rao, director of product management for AWS’ Telco, 5G and EC2, in an interview with SDxCentral explained that the hyperscaler has worked diligently with operators to educate them on the power and capabilities of its public cloud infrastructure. Rao specifically called out work that allowed the AWS platform to carry user plane traffic, which is the link that carries the actual user data between user equipment and the network elements.

“It sort of breaks that barrier of if cloud can meet the performance requirements of the user plane traffic of a 5G core,” Rao said, later pointing to the ability for the platform to support requirements like packet per second processing.

“We believe the user plane [traffic] from our network cloudification perspective is the most significant,” Rao said. “There's nothing such as last frontier, it's a constant journey. But historically this is something which people in the industry have had a lot of questions around processing ability to process user plane traffic. … It's been a great learning experience and a multiyear journey for us. It didn't happen overnight.”

Rao further touted AWS’ moves to support stringent encryption and security requirements. This included AWS’ work to gain third-party affirmation of its Nitro platform to bolster the platform’s security posture. AWS also worked on data encryption at rest, in transit and in process.

This also led to challenges with proving resiliency, which is an important factor for the highly regulated telecommunications industry.

“Can you actually replicate the environment architecturally and from a cost perspective? Do you really need to go and build it the same old way that you would do in your private cloud by creating three replicas of different role-play environment versus just two because you are in cloud and you've got a much higher availability?” Rao said of those requirements.

Rao further explained that the next frontier on this journey is tackling the radio access network (RAN), which is an area of increasing focus for operators looking to break open their extensive RAN ecosystems. As an example of that work, AWS earlier this month struck a deal with open RAN vendor Mavenir to boost their work on making it easier for operators to develop, test and deploy 5G and RAN cloud-native systems in an AWS public cloud environment.

“Our vision is for AWS to be the best place to run 5G networks,” Rao said. “That will mean extending the same cloud continuum across the topology of the network so that once you build the automation you are not worrying about whether it is automation for core or whether it’s for [support systems]. That defeats the purpose. That defeats the purpose of the [total cost of ownership] benefit, of the elasticity benefit. Our objective here is that if customers want to use this for different workloads, they should be able to.”

Analysts do expect these efforts to progress. A report from Dell’Oro Group forecast that hyperscalers like AWS, Microsoft Azure and Google Cloud Platform (GCP) would be hosting 9% of 5G standalone (SA) workloads in their public cloud environments by 2027.

“This is definitely the trend,” ReThink Technology Research’s Whittaker added. “Overall, it will be hard for operators to avoid following this direction because of the scale benefits and access to technologies the public cloud affords them.”