One of the dilemmas of any open networks movement is how to deal with patents licensing and intellectual property (IP) ownership. This will face the Open RAN community, which is already grappling with how to reconcile Chinese contributions to various open platforms, with US technology sanctions against Chinese firms. And more broadly, a robust and trusted IPR approach will be critical to adoption, and to the willingness of vendors and operators to contribute and invest in evolving the fledgling platforms.
One objective of many open technology initiatives in the mobile world is to lower barriers to entry for new vendors and service providers, and one aspect of this is to reduce the stranglehold of a few giants on standards-essential patents (SEP). Beyond that, there is a desire to make the licensing of SEP, and other important patents, more transparent and fair to all. Although SEP must be licensed according to FRAND (fair reasonable and non-discriminatory) principles, these are subject to interpretation, and many licensing deals are still conducted as secretive, bilateral agreements with no visibility on pricing.
The usual ways to throw open IP licensing and royalty levels are either to go fully open source, or to adopt patent pools. These are not mutually exclusive – most commercially adopted open source frameworks include allowance for licensing, so that innovators are not deterred from contributing their inventions by an inability to monetize them.
In reality, the Open RAN platforms are generally far from being open source. The O-RAN Alliance has an open source wing, but this is less active and well-supported than the main organization, and Telecom Infra Project (TIP), which was initially founded around open source, quickly introduced licensing schemes as well. The Open Networking Foundation (ONF) does support open source, and is working on its own implementation of the O-RAN RAN Intelligent Controller (RIC)
Until now, there has been a sense that the Open RAN community is focused mainly on getting its specs and platforms market-ready rather than expending too much energy on licensing rules, but that will only kick a crucial issue down the road, not solve it. And as trials and commercial agreements start to mount, the platform has attracted its first patent pool, called Alium.
Announced just before the holiday, Alium has been established by one of the most venerable hi-tech patents pool operators, MPEG LA, working with Unified Patents. The partners said their goal was to support “the development of Open RAN by providing a solution to the uncertainty and risk posed by the more than 100,000 essential patents already self-declared”.
Alium aims to announce its founder members in the next few months. To qualify to join, a company must have at least one standards-essential Open RAN patent, as validated by an independent expert who will be chosen and funded by the pool. Alium participants will get access to all the SEP held by other participants, and can challenge other patents not covered by the patent pool. According to patents expert Florian Mueller, who runs the Foss Patents website, “this is a unique combination. All other patent pools that I know are neutral with respect to patents outside a given pool”.
Unified Patents will provide AI technology to help decide on the value of patents and how royalties will be calculated. “It is prohibitively expensive and time-consuming to manually review and claim chart each patent that potentially could be essential to the Open RAN standard,” said Alium in its launch statements.
Initially at least, Alium will concentrate on patents in radio units (RUs) that comply with the O-RAN Alliance’s reference designs for indoor picocells and outdoor microcells that use Split 7.2 for the fronthaul link between the RU and the baseband. Fees start at $25 per radio unit and go down to $10 for all units sold after the first 200,000.
It may expand its activities to other parts of the architecture if its initial efforts attract sufficient support.
That, of course, is the deciding factor for any patents pool. A critical mass of IP owners is necessary to make the pool into a standard and there can be significant battles between rival pools, especially in highly strategic technology areas where large vendors are keen to assert their influence. Attempts to establish patent pools for 3GPP device IP have usually fallen apart because of two factors – up to three pools vying for dominance at any one time, with none of them becoming a de facto standard; and the lack of motivation for certain large IP players, such as Qualcomm, to take part and sacrifice their traditional methods of negotiation and licensing.
In other technology areas, such as video codecs, rival vendors have thrown their weight behind competing pools in order to try to dominate the ecosystem – MPEG LA itself has been waging war for almost a decade over codecs, setting its own H.264/HEVC and successor frameworks against alternatives supported by the web giants, notably Google.
It remains to be seen whether Alium secures sufficient support to give MPEG LA a foothold in Open RAN, and if it does show signs of success, whether another organization will launch a challenge. MPEG LA has ventured into cellular SEP before without notable success. It set up an LTE patent pool in 2010, for instance, but had to compete with rival pools established by VIA Licensing (and supported by Google) and by Sisvel. None of them gained enough support to affect how 4G patents are licensed.
So far, most prominent Open RAN suppliers have been reticent about the new Open RAN pool. Nokia said it was too early to comment, while Parallel Wireless told LightReading that “broadening the supply chain and ensuring clear IP rights is a prominent sign of the maturing Open RAN ecosystem driving technical leadership in wireless networks” – but did not comment on Alium specifically.
Some challenger vendors, such as Airspan, said they are considering joining the new pool, though all acknowledge it will only work if some of the largest owners of 3GPP-related SEP agree to join and support the licensing terms. That would certainly make it essential to secure the backing of Nokia and Qualcomm, the largest 3GPP patent holders that are active in Open RAN; but also of some companies that are not developing Open RAN equipment yet, but may have patents in play, such as Ericsson.
Large operators have highlighted uncertainty over IP licensing as an issue that needs to be addressed before they will adopt Open RAN at scale. “Access to SEP on FRAND terms is an important factor as it will limit the uncertainty around IPR infringement challenges that delay the development of new technologies such as Open RAN,” Verizon wrote in a filing to the US government last year. Neville Ray, technology chief at T-Mobile USA, said in 2020: “O-RAN is interesting at this point in time, but there’s a host of unanswered questions around IP.”
There are other IP issues exercising the minds of Open RAN supporters. One is how
far Chinese technology and IP can be excluded from it, if that becomes necessary to satisfy US regulations, given that a significant provider of seed code was China Mobile, and major O-RAN plugfests have been held in Beijing.
The issue took on a new urgency last autumn when the Biden administration added 43 new companies to the USA’s ‘entity list’ (US firms can only trade with listed companies if they gain a special licence, and these are not easy to secure). Of the new additions, 23 were Chinese, and one is a member of the O-RAN Alliance. This company is Kindroid, apparently a subsidiary of manufacturer Kyland Technology. This led Nokia to suspend work with the O-RAN Alliance temporarily because of IP concerns.
Other O-RAN members include all three Chinese mobile operators, all of which have contributed to Open RAN technologies or trials (particularly China Mobile); plus vendor members including ZTE, IT firm Inspur, and Phytium, a chip designer. In total, according to Strand Consult, there are 44 O-RAN Alliance members that are based in China – the largest representation after the USA’s, which numbers 82 firms.
Some stakeholders believe that the best way to ensure Open RAN remains safe from potential security hacks, by any country, is to built it on the most open platforms possible. In their Open RAN technical requirements document, the European ‘Gang of Five’ – Deutsche Telekom, Orange, Telefónica, TIM and Vodafone – said that Open RAN cloud layers should be developed on top of the open source containers framework Kubernetes. “Kubernetes-based infrastructure shall be the mainstream implementation of the O-Cloud platform to host O-RAN functionalities such as O-CU, O-DU and near real-time RIC,” they wrote.
Chinese companies are not excluded from these broad open platforms of course, though they have been less active in open source than their US counterparts – though Huawei has a seat on the Kubernetes Steering Committee and claims to be the technology’s fifth biggest contributor. But open source communities take the view that, with the platform being visible to such a huge number of companies, developers and security experts, it would be far harder for any one member to embed spyware or enable violations, unnoticed, than it would on closed equipment.
Meanwhile, the ‘open source RAN’ remains the stuff of dreams, even according to some of the challenger vendors that are making progress in opening up the cellular ecosystem. Some of this relates to the difficulty of applying classical open source models, as epitomized by the frameworks of the Apache Foundation, to chips and other hardware. But even when it comes to the software element of the virtualized RAN (vRAN), there is very little work being done on RAN network functions that could be downloaded for free to any baseband or radio unit.
For those that believe a true open source model is the best way to throw open the doors to the RAN market, a depressing sight is that of the WiFi sector. The WiFi ecosystem is undoubtedly more open than that of cellular, with a diverse set of vendors of access points and other elements. The openness has helped make WiFi equipment affordable and applicable to a huge range of use cases. But the IEEE and WiFi Alliance, which publish the specifications, are conventional standards organizations; open source efforts such as OpenWrt have been fragmented in their impact; and in many higher end systems, proprietary embedded software remains the norm.
Of course there is plenty of open source code in use in mobile networks, not least in various flavors of the Linux operating system and in elements of NFV and containerisation infrastructure. But so far, opening up the RAN to a broad base of software developers is being achieved through reference platforms rather than pure open source platforms.
These may be defined and distributed by open organizations such as the ONF, or by individual vendors that open up their platforms in order to achieve broad impact for their products and services. An example of the latter is Intel’s FlexRAN software reference stack, which has been extensively used in early vRAN developments and trials.
The RIC is one of the areas where the two approaches are playing out. While the O-RAN Alliance and the ONF are creating open RIC platforms for which many third parties can develop xApps, Intel is working with VMware’s RIC to do the same – an instance of the chip giant building interfaces to other companies’ products to extend the reach and functionality of FlexRAN, with the aim of making it a de facto standard through sheer ubiquity.
Release 1.0 of ONF’s SD-RAN promises a “complete open source RAN solution for developers” spanning the key O-RAN elements – the nRT RIC, the radio unit, distributed unit and central unit (RU/DU/CU), and a framework for developing xApps, the concept underpinning the RIC. This can be implemented entirely virtually or on reference white box hardware. A fledgling SDK is being shared with the O-RAN Software Community (the open source wing of the O-RAN Alliance) to support and promote availability of interoperable xApps that can work with a selection of nRT-RIC implementations.
The RIC is important, in its near-real time flavor, because it potentially opens up critical RAN management functions that were previously embedded. However, it will have to prove it can perform these very demanding functions at the same level as integrated solutions before it will be adopted in large networks. And that barrier to open source is even greater when it applies to the whole radio software, as the demands of 5G get ever-more stringent.
Some argue that the only way that radio software – of sufficient capability to win operator trust for their macro networks – would be made available under a general open source licence would be if a giant like Intel triggered the move. If Intel open sourced FlexRAN, it would be gambling on achieving the kind of dominance of the ecosystem that IBM did with some of the IT technologies it committed to open source in the 1990s.
But it might just split the industry – after all, AT&T put its xRAN code into open source, but while that was a catalyst for O-RAN, that has moved away from general open source licensing. And IBM was, though wounded, still the king of IT back in those days, so its action was more akin to Ericsson open sourcing its radio platform than Intel. A hypothetical open FlexRAN would still need the big RAN vendors on board, just as O-RAN will to achieve maximum scale, and we are still waiting to see the outcome of the game of ‘who blinks first’ between the operators and the largest vendors (with Nokia playing both sides).
For now, ‘open’ organizations focused on the RAN are adopting a hybrid approach. ONF, for instance, uses a combination of elements, some defined by open source organizations and some by standards bodies. Some of its platforms, such as the Open Network Operating System (ONOS) are fully open source and subject to the Apache process. Others rely on licensed technologies.
It offers its developments under two main models:
- Technical specifications include ONF’s reference designs and OpenFlow portfolio of standards, and are licensed under the Foundation’s RAND-Z (reasonable and non-discriminatory) IPR policy for licensing.
- Technical recommendations, which are normative documents that define APIs, data models, protocols, information models and similar. These are open source under the Apache 2.0 system and may be freely used if formally cited, not altered, and not commercially sold.
When TIP was first established by Facebook, it was billed as an open source initiative to drive commonality and scale economics into the telco network. But it became clear that a more nuanced approach was needed to attract companies that had developed highly differentiated contributions. Many small vendors – as well as many operators – remain concerned by the risks that open source brings in terms of quality, control and patent licensing.
One of the start-ups that was chosen, in 2017, to be incubated by Orange under the TIP ecosystem acceleration center (EAC) program was Amarisoft, whose CEO Franck Spinelli said at the time: “We don’t want to let our technology go for nothing. We want money for that.” While Facebook (and others) have open sourced their own contributions to the project, the option of licensing under RAND (reasonable and non-discriminatory) principles is open to any working group or member, and in 2017, Facebook initiated a new TIP group specifically to support RAN licensing.
Meanwhile, the O-RAN Alliance has a two-string approach familiar from the IT industry (and Android), in which an open source community exists alongside a more commercially driven structure. O-RAN started life combining the efforts of two groups, xRAN foundation and Cloud-RAN Alliance, and its current incarnation shows the heritage of both. The former was hosted by the Linux Foundation with seed code open sourced by AT&T, while the latter was more closed.
The O-RAN Software Community is an open source grouping that sits alongside the O-RAN Alliance, and last month published its ‘Cherry’ software release. Cherry contains new functions aligned with O-RAN specifications including the E2, A1 or O1 interfaces, and new service management & orchestration (SMO) elements.