Applying cloud software-based IT virtualization technology with Nokia
Development of core application technologies such as automatic recovery in the event of base station failures and function splitting technology

Base station equipment that exchanges wireless signals with mobile phones has been implemented using general-purpose servers and software and applied to a commercial network for the first time.

SK Telecom (CEO and President Jang Dong-hyun, www.sktelecom.com) announced that it has successfully tested the application of a cloud-based next-generation virtualized base station (SDRAN, Software-Defined RAN) to an actual LTE commercial network at the SK Telecom R&D Center in Bundang, together with global telecommunications equipment manufacturer Nokia (CEO Rajeev Suri).

This virtualized base station implements the functions of existing mobile communication base stations into a virtualized cloud using general-purpose IT servers, and is a new concept of virtualized base station that innovates the base station structure so that the RRU (Remote Radio Unit)* performs some of the functions handled by the existing base station DU (Digital Unit)*.

In particular, with the success of this base station virtualization, SK Telecom has succeeded in virtualizing the entire LTE network, from the core network which is the center of the existing network to the base station which is the final end point, and is evaluated to have completed the foundational technology for the innovation of the communication network structure to 5G.

This virtualized base station is designed so that the RRU, which processes wireless transmission and reception signals, performs some of the functions handled by the DU, which processes digital signals, thereby drastically reducing data volume and enabling long-distance transmission.

In addition, the base station can independently detect system abnormalities, automatically restore it in the event of a failure, and adjust base station capacity according to the number of subscribers connected to the base station and the traffic load.

While existing dedicated communication equipment consisted of proprietary hardware different from each manufacturer, making compatibility difficult and reducing efficiency in network operations, virtualized base stations are evaluated to have lowered communication infrastructure costs and improved communication quality and network stability by adopting general-purpose IT servers.

Since demonstrating the world's first virtualized base station in 2013, SK Telecom has continued to collaborate with Nokia to develop a new type of base station equipment by combining telecommunications infrastructure and IT technology. It has now successfully conducted the world's first commercial network verification for commercial subscribers and plans to expand commercial network verification to other regions within the year.

"By verifying Nokia's AirScale cloud RAN technology on a commercial network together with SK Telecom, we have set an important milestone in the evolution of next-generation networks," said Frank Weyerich, General Manager of Wireless Network Products at Nokia. "We intend to lead the construction of future cloud-based wireless networks, including 5G, together with SK Telecom."

Park Jin-hyo, Head of Network Technology at SK Telecom, stated, “This commercial SDRAN verification is a groundbreaking example of demonstrating core 5G technologies on an LTE network,” adding, “SK Telecom will continue to lead the innovation of next-generation network architecture by consistently developing innovative technologies, such as virtualized base stations, together with various business partners possessing excellent capabilities.”