Marvell Brings Traditional Network Infrastructure Tools To 5G Open RAN

While it may not be as sexy as 5G phones, one of the hottest topics in the telecom world is Open RAN (Radio Access Network). The basic idea with O-RAN (as it is commonly called) is to bring the type of flexibility and choice to network infrastructure equipment that the cloud computing world discovered when it moved away from costly, specialized devices to relatively generic computer servers. In both instances, the effort is happening through a combination of more generalized hardware and standardized interfaces. (See “Will 5G Networks Move To Open RAN?” for more.)

Traditional network infrastructure vendors such as Ericsson, Nokia and, most recently Samsung Networks, have dominated the telco equipment space for decades with mostly proprietary, expensive solutions, often based on specialty chips like FPGAs (Field Programmable Gate Arrays). A big part of the reason has been the enormous complexity of these devices, as well as the critical need for utility-level reliability.

As with many areas in tech, over time these devices have been able to move more of their functionality to a software-based environment, removing some of the dependence on specialized hardware, while at the same time opening up more flexible and (ideally) less expensive options for creating networks. By moving to a more software-focused architecture, the ability to add new types of features and more efficiently use the hardware through virtualization techniques has become significantly easier.

At the same time, a key benefit of dedicated systems is the reliability and consistent level of performance that they provide. In addition, there are no concerns around interoperability, because in most deployments of network infrastructure equipment, all the critical components come from the same vendor. To be clear, most carriers buy equipment from multiple network infrastructure vendors to ensure diversity and competitiveness, but the little-known truth is that they still tend to use all the same vendor’s equipment in one geographical location and a different vendor’s gear in a different place. Very little mixing and matching between network equipment vendors occurs in a given location.

One of the main goals of O-RAN is to enable more flexible combinations of equipment by opening up the interfaces between these systems. The trick is, it has to do that while maintaining the same reliability of the traditional “closed” systems, and that’s proving to be a challenging goal.

Semiconductor maker Marvell took an important step towards helping maintain that reliability by introducing a new line of O-RAN-focused chips that are based on silicon designs currently being used in the more recent software-based network equipment from the traditional makers. In other words, it’s taking key elements from devices such as CUs (Centralized Units), DUs (Distributed Units), and RUs (Radio Units), customizing them for the unique requirements of the Open RAN market, and making them available. The goal, obviously, is to bring the kind of reliability and performance that the traditional infrastructure players have been using and put them into the hands of a new and different set of infrastructure vendors (or even those within traditional vendors who are working on O-RAN compliant hardware).

Specifically, Marvell announced new versions of its Octeon Fusion baseband processors dubbed Octeon Fusion-O (for Open RAN) that take the core capabilities of the part and then add optimizations for O-RAN applications, including the ability to compress and decompress the eCPRI (Enhanced Common Public Radio Interface) signals that pass between a cell tower’s RUs and the CUs and DUs used to process the signals. Traditional closed networks use “regular” CPRI for these signals, but each vendor offers a slightly different (but incompatible) flavor, making interoperability very challenging. eCPRI was developed as an open standards-based interface that could enable Open RANs.

The reason this matters is that the Octeon Fusion parts are currently integrated into traditional network infrastructure equipment and are deployed across multiple LTE and 5G carrier networks around the world, making them a well-known, well-understood part of traditional networks. Leveraging these existing capabilities into the Octeon Fusion O chips not only adds credibility to the solution, it also makes it easier to integrate software, originally developed to work on the Octeon Fusions, into new O-RAN solutions. In fact, part of Marvell’s O-RAN offering includes software to help with this process.

Marvell is making the Octeon Fusion O parts available both as standalone components for inclusion into integrated DU designs, or as virtualized DUs in the form of a PCIe-based accelerator card that plugs into x86-based servers that can be used to run other aspects of a 5G core network.

In addition to the Octeon Fusion O parts, Marvell also unveiled a multi-MIMO (Multiple Input, Multiple Output) RU design in conjunction with Analog Devices. The design offers up to 32 channels of simultaneous transmission and reception, a first for O-RAN applications, and a critical tool to help with the “densification” of 5G networks. (See “How Will 5G Networks Get Faster? Densification” for more.) Finally, the company also debuted a new Ethernet switch chip called the Prestera DX 7300 that’s intended to be used as a component with these 5G O-RAN systems and reference designs.

All told, it’s a fairly complete set of tools that should bring new levels of credibility and reliability to the 5G Open RAN marketplace. Of course, even with these increased assurances, O-RAN continues to face a bit of an uphill battle with established “brown field” carriers that have large amounts of traditional infrastructure equipment in place. It can be very expensive and technically challenging to make the transition from “closed” systems to open ones. Plus, some carriers have expressed concerns about the fact that it can often take the efforts of multiple vendors to pull together a complete solution, leaving them without a single throat to choke should a problem arise. As a result, a lot of the early success for O-RAN has been with new “green field” carriers, such as Rakuten in Japan, or in the burgeoning market for private 5G networks, which all have to be built from scratch.

Over time, however, the speed, flexibility, and cost benefits are likely to lead to much more rapid adoption of O-RAN technologies even among existing carriers. Marvell’s new offerings look to provide an important step in that direction.

Disclosure: TECHnalysis Research is a tech industry market research and consulting firm and, like all companies in that field, works with many technology vendors as clients, some of whom may be listed in this article.