C-RAN Gets Serious

By Iain Gillott, contributing editor

March 15, 2018

The act of Nokia joining the membership organization xRAN, puts pressure on other manufacturers to demonstrate a viable, open radio access network (RAN) architecture. It would improve the chance of getting cloud RAN deployed for outdoor cells.

The promise of cloud radio access network (C-RAN) technology has always been great, but what was needed was the support of one of the major radio and base station original equipment manufacturers. After all, for the last three decades or so, mobile operators have purchased outdoor RAN equipment for a specific market from a single vendor, because the interfaces between the various RAN components are not generally open.

When small cell architectures were first discussed, many believed that those architectures would open up the RAN to other vendors. But when it came to implementation, the same proprietary interfaces were still there, and the outdoor small cell vendors were all forced to look for new markets in-building. As a result, the Long Term Evolution (LTE) RAN market consisted of the same RAN vendors. After a series of mergers and acquisitions, we are now left with five vendors who operate globally: Ericsson, Huawei, Nokia, Samsung and ZTE. All are stronger or weaker in various markets, and the vast majority of operators buy RAN equipment from one or more of these vendors. Some operators (usually operating in rural markets) have deployed other vendors for specific markets; Vanu is a good example.

Virtualization of the mobile network has started with the core and slowly expanded outward toward the RAN. The RAN is generally seen as the last part of the network to be virtualized, with the deployment of a virtual baseband unit (vBBU) and radio using off-the-shelf components with open interfaces. Just as virtualization has reduced the cost of deploying and maintaining an Evolved Packet Core (EPC), so the goal is the same for the RAN — reduced capital expense (capex) and operating expense (opex).

xRAN, a membership organization named after extensible RAN (xRAN), provides a good example of the current work going on in RAN virtualization. The goal of the industry group is simply to develop, standardize and promote a software-based, extensible RAN and to standardize critical elements of the extensible RAN architecture. xRAN members include some of the biggest and most advanced operators in the industry: AT&T Mobility, Deutsche Telekom, Telstra, Verizon Wireless and SK Telecom. Note that these operators have been pushing virtualization hard and are also moving ahead to 5G as quickly as possible. xRAN vendor members include Intel, Cisco, Mavenir, Amdocs and others.

What has been missing industry groups involved in the open C-RAN debate is the involvement of the big RAN OEMs. Without one or more of the big vendors willing to move to an open C-RAN architecture, there is little chance of getting C-RAN deployed meaningfully into the major markets for outdoor cells.

So now the big news: Nokia has joined xRAN. The Finnish company has been working behind the scenes for a few months and has now executed all the necessary paperwork (and, I assume, has written a check for the dues).

When I discussed this news with someone in the industry, their first reaction was skepticism, because the major OEMs have joined similar virtualization and open forums in the past, only to use the opportunity as a fact-finding exercise without making any changes in their strategy or the openness of their products. But having spent a week in December in Finland at Nokia’s industry analyst event, I concluded that Nokia is sincere: The company has made a big move to cloud architectures using open interfaces, and xRAN is the latest development with this strategy. In short, it does not appear that Nokia is simply in this to sit back and listen, but to contribute to the forum and move toward open RAN interfaces as quickly as possible.

It is also worth remembering that building, optimizing and operating radio networks is always harder than it appears. Although some people draw comparisons to Wi-Fi, LTE and soon-to-come 5G are completely different animals. 5G will support network slicing and prioritization of traffic. All cellular networks hand off between cells to (hopefully) maintain the connection. These all add complexity to the network and operators. As such, Nokia and its major OEM competitors have considerable experience and expertise building and operating networks, expertise that will be as valuable as it has ever been as the industry moves to 5G.

Nokia is unlikely to lose its place in the industry simply because the company is moving to open RAN interfaces. With open architectures and virtualized 5G networks, there are considerable opportunities for network analytics, optimization and professional services. There will be no shortage of things to do.

The question now is, assuming this initiative is successful and continues to make progress, what will Samsung, Huawei, ZTE and Ericsson do. Nokia’s move has put pressure on the other OEMs to follow suit, if not by joining xRAN, then at least by demonstrating a viable, open RAN architecture. 2018 is going to be interesting.

Read the rest of the March AGL Magazine HERE.

Iain Gillott is the founder and president of iGR, a market strategy consultancy focused on the wireless and mobile communications industry. The company researches and analyzes the effect new wireless and mobile technologies will have on the industry, on vendors’ competitive positioning and on its clients’ strategic business plans. Visit www.igr-inc.com.