Vodafone and DOCOMO serve up white paper on Open RAN systems integration

Vodafone and NTT DOCOMO, INC. (DOCOMO) today published a joint white paper (see below) offering advice to the wider operator and vendor community when testing the integration of key Open RAN software and hardware building blocks.

It is the first in a series of recommendations following Vodafone and DOCOMO’s recent pact to cooperate on harmonising mobile operator system integration and test processes. This white paper is designed to smooth the path for operators and vendors to more quickly and efficiently build and scale Open RAN systems and will be aligned with ORAN Alliance and Telecom Infra Project to address the challenge collectively. It specifically addresses testing criteria and experiences to create common test scripts (a series of software instructions needed to conduct a test), as well as the need for greater cooperation and information sharing.

Avoid repetition

By adopting a uniform approach to testing, vendors can avoid repetition when dealing with multiple operators, saving them time, money, and resources. They can also deliver ‘secure by design’, high quality products as defined by the industry bodies - 3GPP and the ORAN Alliance – no matter the region.

A focus of the white paper is on the integration of Open RAN Radio Units (O-RU), which convert phone signals into digital data to be processed and sent via compatible Distributed Units (O-DU) to its destination (such as a distant server) via the core network. The performance level of an Open RAN base station hinges on RU and DU components being blended perfectly using the same set of specifications.

Unblocking bottlenecks

Currently, it can take up to nine months or more to onboard and integrate new O-RU/O-DU combinations in the lab, leading to bottlenecks in the commercial production line. Reducing the time and cost to test and debug the O-RU/O-DU integration is key to expediting the rollout of Open RAN.

Engineers from Vodafone, together with like-minded experts from DOCOMO, have combined their collective testing experience to identify several root causes that can frustrate O-RU/O-DU conformity. Either using different versions of industry specifications or simply misinterpreting them are common mistakes.

Be prepared

In the paper, Vodafone and DOCOMO acknowledge that responsibility lies with the operators to improve the journey and have committed to bringing their automated scripts and test solutions to the table. Based on several years’ experience, both companies recommend appropriate paths for a vendor to take depending on which part of the Open RAN jigsaw they are developing. It is hoped this will help vendors automate their own scripts to rapidly check that their O-RU/O-DU interfaces are compliant. This will give them confidence that their product is ready for interoperability testing at either an operator or community-led lab, avoiding any unnecessary delay.

Automation is not enough

But automation alone is not enough. It is vital that all parties make an effort to collaborate and leave behind any protectionism. Through trust and greater collaboration, systems integration will become a streamlined process allowing the new ecosystem to thrive for both established and new vendors.