Mobile tech explained: Interoperability

This article is part of a series breaking down the complex systems and technologies that make up the Rakuten Mobile network and Rakuten Communications Platform. In this edition, we speak with Rahul Atri, head of product and engineering, Rakuten Mobile.

In the technology and telecoms sectors, there is an ongoing tug of war between innovation and interoperability. A start-up might develop a fantastic new technology that is better or quicker than anything that has come before. But if that technology doesn’t work with existing systems, it can be very difficult to deploy.

As it has developed and deployed its groundbreaking cellular network in Japan over the past three years, Rakuten Mobile has been wrestling with the challenge of pursuing innovation and interoperability (interop) at the same time.

During that period, Rakuten Mobile has become adept at integrating technologies from different vendors, including more than 200 individual network applications. “We have made a lot of choices, some of them by design, some of them by failure,” says Rahul Atri, head of product and engineering for Rakuten Communications Platform. “I spent a lot of sleepless nights in the office. But we found it is okay to have as many partners as you want to. As long as the partner is aligned with us, we can solve interop together.”

Creating a common language and frameworks

We have built frameworks, templates and integration platforms. Today, if we need to replace one of our partners with another one, we know what to change. For the radio network, for example, we had to go through 10 to 12 different spreadsheets of parameters, values, rules and logic. We went through the detail of each and every parameter: What is static, why it is static, what is dynamic and why it has to be dynamic.

Rahul Atri, head of product and engineering for Rakuten Communications Platform.

To enable software and hardware from different vendors to be onboarded and integrated seamlessly, the product teams at Rakuten Mobile design product frameworks upfront. That includes templates, policies, interfaces and payloads. This DNA and thought process is not limited to onboarding, but to operations as well.

By working hand-in-hand with its suppliers, Rakuten Mobile acquired the detailed expertise it needs to be able to mix and match the best applications, systems and solutions. “We have built frameworks, templates and integration platforms,” explains Atri. “Today, if we need to replace one of our partners with another one, we know what to change. For the radio network, for example, we had to go through 10 to 12 different spreadsheets of parameters, values, rules and logic. We went through the detail of each and every parameter: What is static, why it is static, what is dynamic and why it has to be dynamic.”

Rakuten Mobile had to do this work in-house because no other operator in the world had deployed a fully cloud-native open RAN mobile network before – there wasn’t a body of existing knowledge it could tap into. “We did it end-to-end,” explains Atri.

Rakuten Mobile’s hands-on approach has enabled it to employ innovative technologies developed by ‘challenger vendors’ such as Altiostar, Robin.io, Airspan, QCT and NEC, rather than simply deploying monolithic systems from the major vendors.

A new playbook for cloud-native networks

Rakuten Mobile had to do this work in-house because no other operator in the world had deployed a fully cloud-native open RAN mobile network before – there wasn’t a body of existing knowledge it could tap into.

By building end-to-end frameworks that support interoperability, Rakuten Mobile is developing a playbook to guide other operators who want to deploy an advanced cloud-native network using technologies from multiple partners. Those playbooks are part of the Rakuten Communications Platform (RCP).

The RCP marketplace offers apps for the entire telecommunications network lifecycle, from planning and building to operating and enhancing. It also hosts apps for network related tasks such as asset management, OSS, BSS, workflows, rollout, field force management, orchestration, observability, ticket and incident management.

The platform itself is built on an API-centric approach, using configuration templates. It is app, service and vendor agnostic. This means mobile network operators can work with the technology partners of their choice from the various options available on the marketplace, and configure apps for various network tasks according to their own specific needs.

Moving in an open source direction

Over time, the telecoms sector is likely to make greater use of another key feature of the IT world – open source technology. Developed, tested and refined by a community of contributors, open source systems benefit from economies of scale, as multiple entities share their work and ideas for new features and enhancements.

Rakuten Mobile is looking to deploy open source systems where it can, and Atri is optimistic that the telco ecosystem will eventually adapt to this mindset. “I think it’s the responsibility of all service providers to come together and build an ecosystem where people feel okay to share, okay to expand, okay to go for open source and sometimes okay to fail,” he says.