Samsung and Radisys boost ORAN’s quest for a multivendor 5G RAN

The changes in the RAN which operators are hoping to see as 5G matures give Samsung its best, and probably last, chance to have a major impact on the mobile network market. Its track record in fixed wireless access (FWA) gave it a position in the early US 5G roll-outs, which started with an FWA focus; Huawei’s troubles have led some MNOs to build up the Korean company as an alternative counterweight to Nokia and Ericsson.

However, outside its home market and FWA, Samsung has a very small installed base compared to the big three, and almost no position in Europe (where its flagship customer, Three UK, is ripping out its 4G equipment and replacing it with Huawei 4G and 5G gear). It is well-regarded for its developments in some key 5G enabling technologies such as Massive MIMO and Cloud-RAN, but it lacks the economies of scale which help its rivals to be price-competitive; and its lack of an entrenched position means it is harder to persuade MNOs to take a risk on a brand new supplier at the 5G stage.

It is essential for Samsung, then, to play to some of the operators’ biggest objectives for 5G, especially those where Huawei, Ericsson and Nokia may be lagging behind because of conflicts of interest. The most obvious is the open RAN – a fully interoperable set of standards in areas like fronthaul is an important goal for many MNOs, because it would allow them to deploy multivendor disaggregated networks and so introduce more competition into their supply chains. Though Nokia has been supportive of one of the biggest initiatives in this area, the Linux Foundation’s ORAN Alliance, there are clear conflicts for the big OEMs, which have relied on locking their customers into their architectures and so keeping prices, and barriers to competitors, high.

Samsung has none of those dilemmas and can present itself as a challenger, which can use multivendor standards to infiltrate networks supplied by others; but it has sufficient scale and technological resources to reassure operators. Despite the support that Orange, Deutsche Telekom and others have given open network start-ups like Athonet, it remains unlikely that they would entrust a small provider with a large element of their central network deployment, or that the newcomers would have the scale to support that effectively.

Samsung said last week that it had been focusing, in its 5G developments, on “open interfaces within radio access networks”. It has worked with the two main open RAN initiatives, ORAN and the Telecom Infra Project’s (TIP’s) RAN working groups. It is also working on opening up the CPRI and X2 interfaces for fronthaul and centralized RAN, according to Alok Shah, VP of networks strategy and marketing at Samsung Electronics America.

These two interfaces are officially standardized, but have been implemented differently by each vendor, limiting interoperability. CPRI is the main interface used to link shared baseband units (BBUs) with remote radio units (RRUs) at the cell sites, though alternatives are emerging based on Ethernet.

X2 supports handover between 4G base stations – and will also support handover between 4G and 5G – but even Nokia’s CTO, Marcus Weldon, admitted:“Each vendor tends to implement it slightly differently to get superior performance on their own systems.”

Samsung joined the ORAN Allliance in February and Shah expects commercial ORAN networks to be live by early 2020, supporting a standard fronthaul interface, and running RAN baseband processes as a virtual network function on commodity hardware.

Another boost for the ORAN Alliance came with the news that Radisys would contribute its Open 5G seed code to the project. The protocol stack supplier has become a key contributor to open initiatives such as the Open Networking Foundation’s CORD (Central Office Re-architected as a Datacenter). Now it will work with AT&T, China Mobile and Intel to define ORAN’s 5G New Radio (NR) stack reference architecture, building on its existing Open 5G code.

Radisys said this work would accelerate the creation of a broad ORAN ecosystem and enable the delivery of open application programming interfaces (APIs) and open architectures for 5G.

The four partners co-chair the Alliance’s Work Group 8, whose role is to define the 5G NR stack reference architecture. “We share a common vision with our WG8 co-chairs – China Mobile, AT&T and Intel – to accelerate RAN evolution through the principles of disaggregation and openness, while laying the groundwork for 5G networks that are being built today,” said Neeraj Patel, general manager of software and services at Radisys.

He added that the new effort was “reaffirming our own commitment to the open telecom revolution, and we call on other vendors and operators to make their own contributions to this important work.”

China Mobile’s chief scientist, Dr Chih-Lin I, added: “We are also committed to contributing code to the O-RAN SC community. China Mobile believes that the open source RAN software will play an important role in promoting the prosperity of an open ecosystem.”

Radisys was acquired a year ago by Indian operator Reliance Jio, which has also been very active in driving open source and software-centric platforms to reduce its cost and time to market. It participates in TIP and ONAP and has spoken in the past about open sourcing its internally developed self-organizing network (SON) technology, JioSON.

By paying about $75m to acquire Radisys, it gained a leading light in one of the most important open operator-driven projects, CORD. Akash Ambani, RJio’s director, was clear in his statements that the deal was about disrupting the competitive landscape and the supply chain, not merely about getting control of some useful technologies. “Reliance and Jio have been disrupting legacy business models and establishing new global benchmarks,” he commented. “This acquisition further accelerates Jio’s global innovation and technology leadership in the areas of 5G, IoT and open source architecture adoption.”

He said Radisys’s engineers would enable RJio to tap into skills and innovation worldwide, and influence global developments, not just those in India. In particular, and with a firm nod to CORD, he highlighted “our work towards software-centric disaggregated networks and platforms, enhancing the value to customers across consumer and enterprise segments”.

Radisys’s roots lie in ATCA blades and other infrastructure, and it expanded into protocol stacks and small cell software when it acquired Continuous Computing in 2011. Its sales in these core areas have fallen over the years and it has been lossmaking.

It has been seeking to rejuvenate its financials by moving into higher value businesses, notably implementation and integration services related to open source platforms like CORD.

The CORD project reflects many of the concerns of forward looking operators, especially how a virtualized telecoms network can support distributed cloud services and edge compute. This is a particular preoccupation of RJio’s, which has worked with Cisco and others to leverage MEC (Multi-access Edge Compute) for optimized video experiences. For instance, the MNO has integrated a mobile content delivery network (CDN) into its 4G network with edge caches in close proximity to the users, delivering content via edge cloudlets to reduce latency. The solution implements 3GPP standard Control/User Plane Separation (CUPS) to provide greater flexibility in the choice of user planes.

In future Jio believes the same architecture will be used for low latency IoT and mission critical services, and deeper involvement in CORD will help to achieve edge compute goals.

CORD includes open reference implementations for residential, enterprise and mobile access based on open source SDN, NFV and cloud technologies. It started life as part of the ON.Lab open source project, which also includes ONOS, and that has subsequently merged with the Open Networking Foundation (ONF).

It is part of the ONF’s mission to create an SDN platform that is specifically optimized for carriers, rather than adapting something which was originally conceived for enterprises, like the more established, and vendor-driven, OpenDaylight. Like many open source telco projects, CORD is hosted by the Linux Foundation.

CORD’s aim is to enable the telco central office to function as a data center in a distributed and virtualized environment, supporting cloud services including the telco’s own virtual network functions (VNFs) and edge compute nodes. It supports SDN, NFV and elastic cloud services and integrates with other relevant open sources efforts such as OpenStack, ONOS, Docker, Kubernetes and XOS, all running on white box switches and open compute hardware – including Radisys’s own DCEngine – and on merchant silicon.

The CORD community includes service providers such as AT&T, China Unicom, Google, NTT, SK Telecom and Verizon, as well as vendors Ciena, Cisco, Fujitsu, Intel, NEC, Nokia and Samsung.

In 2016, Radisys donated its virtualized EPC (evolved packet core) to the mobile strand of CORD, putting its flag firmly in an increasingly competitive ground. The following year, Mavenir also contributed a vEPC design and the two vendors demonstrated interoperability – a key MNO requirement to adopt any new architecture, and an important driver for many operators to virtualize at all.

In offering the vEPC under an open source licence, Radisys hoped to gain higher exposure for its technology, accelerating adoption, and thereby to monetize it via integration services. Along with Mavenir, it has been addressing one of the three main elements of the mobile CORD framework – disaggregated and virtualized EPC and RAN, and mobile edge services.

In 2017, Radisys rebranded itself ‘Open Radisys’ to highlight its work in CORD and also the Facebook-led Open Compute Project (OCP), in which RJio is also active (as well as its companion project, TIP). The company said it was aiming to become a major integration partner for telco data center infrastructure.

In November, it listed its achievements so far related to CORD, which include several operator collaborations that may be very valuable to RJio, to deepen its relationships with other MNOs and propel itself into the heart of the open MNO ecosystem.

Those milestones were:

  • A deal with Verizon for Radisys’s FlowEngine Intelligent Traffic Distribution System as the front end for the operator’s SDN service delivery platform.
    • The OCP’s adoption of its CG-OpenRack-19 specification, the basis for Radisys’s DCEngine product.
    • Collaboration with China Unicom on Mobility CORD implementation for 5G services.
    • A Multi-Access CORD proof-of-concept combining wireless and wireline access infrastructure.
    • An alliance with Calix to deliver the first commercial Residential CORD platform.

Radisys CEO Brian Bronson said he wanted to be “the Red Hat of telco infrastructure”, adding: “We open sourced our EPC, we open sourced our RAN, we just got approval that our submission is the telco de facto standard for OCP, so the CG-OpenRack-19 is our DCEngine product,. We do have our own products and capabilities but it is really the integration capabilities that we are highlighting moving forward, like CORD.”

The company also offers CellEngine family, which supports disaggregated RAN software and services to help build a bridge from LTE to 5G. Now called MobilityEngine, this will be of high interest to RJio, which already sports a flexible, distributed network including small cells from Airspan, and uses some of Radisys’s software. MobilityEngine is an “open 5G RAN platform and services offering that supports LTE-Advanced network deployments today, while delivering an easy migration path to 5G,” says the firm. The platform is based on Verizon’s 5G Technical Forum’s specifications and is now migrating to 5G New Radio (NR) too.