• Hopes are high that 6G will drive Open RAN adoption, but it’s far from certain
• 3GPP is engaging with the O-RAN Alliance, yet open fronthaul remains contested
• Operators and vendors are split on referencing O-RAN specs in 6G standards
• Without agreement, multiple fronthaul options could add 6G complexity

There is great expectation and hope that Open RAN will ‘come of age’ with 6G. After cautious progress with 5G network deployments – probably far more cautious than supporters had hoped for – wide-scale commercial success will likely require a major infrastructure upgrade cycle, such as that provided by the arrival of the latest ‘generational’ cellular standard. Maybe. But maybe not.

Over the past several years, TelecomTV has documented the huge amount of work done with Open RAN and, in particular, its development under the O-RAN Alliance. Just visit our channel and take your pick of videos, summits, articles and reports. Time and again we hear that Open RAN’s time will come with the arrival of 6G, and this generational technology change will be the catalyst for industry-wide adoption of Open RAN. Not enough commercial deployments today? Don’t worry, 6G will make it all right.

First of all, we have yet to define 6G. Studies are now officially underway at the 3GPP, following two well-attended workshops this year and the quarterly technical specification group (TSG) meetings that were held in Prague in June, with actual standards work to follow in around 2027. But the 3GPP members are taking Open RAN very seriously, which is why the second workshop was purely devoted to the technology and held in partnership with the O-RAN Alliance. Our report on this event is ready to go and should find its way onto TelecomTV very soon. In the meantime, our series of reports from the first workshop are available here.

Secondly, any attempt to incorporate aspects of Open RAN into 3GPP Release 21 (aka 6G) standards are going to be met with some degree of resistance – and we are already seeing this happen.

The joint 3GPP and O-RAN Alliance workshop was explicitly undertaken to share information about the two organisations, to invite suggestions for interaction and collaboration and to establish a high-level understanding of the work split between 3GPP and the O-RAN Alliance. No firm decisions or commitments were – or could – be made by either organisation.

The O-RAN Alliance is not as transparent with its activities as the 3GPP (who should be applauded for their openness). What we do know though, is that the Alliance sent a letter to the three 3GPP TSG meetings in June – the RAN, SA and CT groups – and informed 3GPP of its post-workshop discussions. It confirmed that it was “committed to the collaboration with 3GPP and has endorsed the parts of the chairs’ summary that had consensus at the workshop”. 

However, knowing that open fronthaul was going to be a subject of the Prague meetings, it cautioned that “it is crucial that 3GPP’s approach to the lower layer split (LLS) in 6G architecture and corresponding efforts in O-RAN Alliance are aligned to ensure consistency”. It requested that 3GPP RAN and SA groups also consider endorsing the parts of the chairs’ summary that had consensus at the joint workshop, as well as considering the "objective for alignment" with LLS standardisation for 6G.

Open fronthaul is going to take some serious negotiating power. This is where it gets sticky. During the workshop, some stakeholders (operators and vendors) proposed to include a radio unit (RU) as a standalone entity in 3GPP RAN architecture and reference the O-RAN Alliance fronthaul specifications in the broader 3GPP specifications. Others did not. An incredibly complex compromise was discussed but, as all stakeholders concluded, these proposals need further discussion.

The 3GPP RAN group was the first to consider the O-RAN Alliance letter. A group of 14 operators co-signed a contribution to the TSG RAN 108 meeting in June, underlining the “critical importance of open interfaces and the referencing of O-RAN [Alliance] specifications”. Note the “referencing” – they are very clear that they don’t wish to see a mandated solution.

These 14 signatories were: NTT Docomo, AT&T, Boost Mobile Network, Deutsche Telekom, KDDI, MobiFone, Orange, SoftBank, Telecom Italia, Telefónica, Telstra, TELUS, UScellular and Verizon.

The RAN meeting chair asked which delegates had “serious concerns” with the proposal. Five companies made their feelings known, according to the minutes: Huawei, ZTE, China Unicom, the China Academy of ICT (CAICT) and KT of Korea.

The concerns from Huawei and ZTE are predictable. After all, Open RAN has been seized upon by many western governments as a tool to remove Chinese vendor equipment from telecoms infrastructure. But at least this clears up any doubts...

[Update, 19 August: KT has kindly got in touch to clarify why it was on the list of companies concerned about the proposal. KT’s concern was not with the 3GPP referencing Open fronthaul from O-RAN, but with having multiple solutions for the DU-RU interface for 6G. This was discussed during the meeting and lead to the suggestion that: “Implementation of this interface can be according to proprietary solution(s), or standardised solutions as specified in O-RAN Alliance”. As KT already stated during its earlier 6G workshop presentation, the telco’s acceptable way forward is to have “standardised solution specified in O-RAN Alliance only”. KT stressed to TelecomTV that it is “fully committed to delivering 6G Open fronthaul to commercial network as multivendor interoperability is the key to success for the global 6G commercial services”. We are happy to clarify this position.]

In an attempt to get some agreement in place, offline discussions were held and the results fed back to the RAN meeting. Under the stewardship of Nokia, new wording was proposed that could be used as the basis for further discussion at the next quarterly RAN meeting, to be held in September. Huawei reiterated that there should be no endorsement at this stage, and that a proposed liaison letter from 3GPP TSG SA to the O-RAN Alliance should not talk about this discussion externally. 

And so to the SA group. During its discussion about the joint workshop and the letter from the O-RAN Alliance, tensions appeared to be as equally high as during the earlier RAN meeting. This all resulted in a brief reply to O-RAN Alliance that stopped short of saying it endorsed the workshop summary, and instead replied that it “accurately captures the high -level principles”. It then informed the Alliance that “TSG RAN has further discussed 6G fronthaul interface and will continue discussing the issue with the aim of resolving the issue at TSG 109”.

Open fronthaul means operators can mix and match RUs across vendors, reducing vendor lock-in and creating competition. Just look at the news this week from AT&T and its first data call over Open RAN third-party radios.

Admittedly, we are only in the study phase, but it is an important stage in the development of 6G. A lack of agreement over fronthaul will likely result in multiple options being specified – and we already know from the first 6G workshop that operators absolutely do not want to be confronted with the levels of complexity, choice and waste that accompanied 5G. They want it simple; they don’t want standards complexity and they absolutely don’t want market fragmentation.

Of course, Open RAN technology and O-RAN Alliance specifications will be available to whichever vendors and operators want them, irrespective of the final normative 3GPP 6G standards. It is massively improbable (nor would it be generally welcomed) for Open RAN to be mandated in 6G standards, there’s no desire for this, but an alignment with 6G and some sort of integration or provision would provide a huge boost to the Open RAN ecosystem and would strengthen investment confidence. That’s a goal worth fighting for.

- Guy Daniels, Director of Content, TelecomTV

Updated with comments from KT on 19 August 2025.