• Group’s tech boss likens RAN disaggregation complexity to landing a space rocket booster.
  • Delayed SD‑RAN trial one of many remaining legs on “journey” towards open RAN maturity.
  • DT acknowledges geopolitical challenges around O‑RAN ecosystem.
  • Call-to-action made on collaboration.

Deutsche Telekom's Choi sees open RAN deployments from 2023

Deutsche Telekom’s Choi sees open RAN deployments from 2023

Source: Marco Verch / Flickr CC BY 2.0

Dr. Alex Jinsung Choi, SVP of Strategy and Technology Innovation at Deutsche Telekom, indicated that DT’s ambition is to make open radio access networks a “deployable option in our footprint starting from 2023 onwards, with a focus on deployments at scale”.

DT has “embarked on the first phase of our open RAN journey”, Choi said, while noting that open RAN is not yet a mature technology. “There are gaps to close before open RAN is capable of delivering the best RAN capabilities at scale, and automation is a must‑have to manage this complexity in the disaggregated network”, he said.

Choi was discussing open RAN progress following the October 2021 launch of the SD‑RAN Berlin Trial project by DT and the Open Networking Foundation.

Described as the first field trial to implement fully disaggregated open RAN solutions using ONF’s RAN Intelligent Controller (RIC) software platform, the 4G and 5G standalone system is live at a DT site in the German capital. Choi said the project is a first step in the operationalisation of open RAN. The next will involve the ongoing development and integration of external applications (xApps) from the ONF community, followed by field trials in 2023. “There’s a long way to go, and there are no shortcuts to doing this right”, he said.

Five-point plan

Choi outlined five key components that are supporting the Group’s progress towards open RAN deployments, including:

  • DT’s O-RAN Town deployment in Neubrandenburg, Germany (Deutsche Telekomwatch, #106).Work on creating an independent service management and orchestration (SMO) approach to avoid vendor lock‑in and manage the complexity of multi‑vendor integration;
  • Fostering a “vibrant and sustainable supplier ecosystem”;
  • Developing the required inhouse skills and resources;
  • Implementing a ‘product house’ to build DT’s entire integration capabilities.

Choi also reiterated the ongoing need for collaboration among vendors and operators. For example, he pointed to the signing earlier this year of a Memorandum of Understanding (MoU) on open RAN promotion by DT, Orange, Telecom Italia, Telefónica, and Vodafone. He also highlighted DT’s engagement with numerous industry groups, including the ONF as well as 3GPP, Cloud Native Computing Foundation, O‑RAN Alliance, The Linux Foundation, Open Network Automation Platform, Open Network Compute, and Telecom Infra Project (TIP).

Choi himself is COO of the O‑RAN Alliance and one of the Alliance’s founding members. He described the SD‑RAN Berlin Trial as an example of how collaboration can work, and advocated even closer relationships between groups such as ONF and the O‑RAN software community. Choi indicated that DT planned to share important findings from the Berlin trial at the O‑RAN Plugfest that took place this week.

It doesn’t help anyone if we are reinventing the wheel”, he said. “The disaggregation of networks is cutting edge and challenging… With so many moving parts all arriving at different times, with a different level of maturity, the reality is much, much more complicated. I compare the complexity of RAN disaggregation with the challenge of landing a SpaceX rocket booster on a very small platform in the sea”.

Bumps in the road

Choi’s observations on the timeline for open RAN chime with those made in July by Carlos Fernandes, VP of Group Technology Innovation at DT, who said he expected open RAN and disaggregation adoption to “ramp up” in 2021, and the pace of deployment to increase in 2022 and 2023.

With regard to some of the more unexpected challenges along the way, apart from the impact of the coronavirus pandemic, Choi referred to the geopolitical problems that, among other things, recently saw Nokia halt technical activity in the O‑RAN Alliance because of several Chinese participants being added to the US “Entities List”.

There also been some question about whether the O‑RAN Alliance as a spec is a really a global standard. We’re still working on it, and especially we are also working very closely with the existing global standard bodies like ETSI to handle this risk”, he said.

Rüdiger Kunze, Head of Cost Engineering, Standards & Process Services at DT, indicated that the SD‑RAN Berlin Trial itself had been delayed by around six months. This was in part owing to the pandemic, but was also because of supply chain challenges, the complexity of the technical set‑up, and the need to coordinate with the various partners.

The trial is now up and running, but this multi‑component system still needs stabilisation and hardening, so this is really where we have to focus within the next couple of months”, Kunze said.

This is not a sprint, it’s a marathon. We are still at the beginning of a new technology generation. And this is not a black‑box approach; it’s a multi‑component hardware and software orchestra delivered by a huge ecosystem of partners … This trial is a great opportunity to transfer knowledge from the SD‑RAN trial and SD‑RAN project of the ONF to the O‑RAN”, Kunze concluded.

The SD‑RAN Berlin Trial hosted by DT integrates components from eight vendors: AirHop, Edgecore, Facebook, Foxconn, Intel, Radisys, Supermicro, and Wiwynn. Additionally, TIP is providing hardware and facilities from the TIP Community Lab in Berlin that is also hosted by DT (Deutsche Telekomwatch, passim). The on‑site field trial integration and testing is being coordinated and supported by Highstreet Technologies. The live trial features horizontally disaggregated hardware, as well as vertically disaggregated software components including an open source near real‑time RIC (nRT-RIC) and xApps (external applications that control aspects of the RAN) from the ONF’s SD‑RAN project. The trial uses the ONF’s multi-cloud, cloud-native platform, Aether, and highlights network slicing, with multiple user plane functions running at the edge.

SD‑RAN is ONF’s exemplar platform for 3GPP‑compliant, software‑defined RAN and is consistent with open RAN architecture. It is cloud‑native and uses several ONF platforms including the Open Network Operating System software‑defined networking controller.