| Provides priority 5G network to 5G service subscribers
Reduced transmission latency from 18ms to edge communication center to 10ms
Security enhanced with Giga Stealth and Network Slicing technology

KT held a press briefing on 5G network technology on the 26th ahead of the launch of its commercial 5G service this coming April. At the event, KT highlighted four key keywords for its 5G network: the largest coverage in Korea, a user-centric '5G First' strategy, ultra-low latency, and battery saving technology.

In time for the launch of commercial services, KT has prioritized the completion of 5G network construction across Seoul, the metropolitan area, six major cities, parts of 85 cities, and 70 large shopping malls and department stores nationwide that are major densely populated areas. In addition, 5G networks have been built on major transportation routes connecting these areas, such as ground sections of KTX and SRT, the entire Gyeongbu and Honam Expressways, and six airports nationwide. KT stated that it is the only operator to have announced the construction of a 5G network on major inter-regional travel routes.

In addition, KT has completed the construction of 5G coverage at 464 university campuses and nearby areas nationwide, as well as at major industry-academia-research sites including Hyundai Heavy Industries in Ulsan and K-City in Hwaseong, to foster a 5G technology ecosystem through industry-academia-research cooperation.

KT plans to expand its 5G network to cover most areas of 85 cities by the end of this year, and plans to secure in-building coverage in major buildings such as subways, government offices, and university hospitals nationwide, including Seoul and the metropolitan area.


Providing customer-first 5G networks with the 5G First strategy
KT announced that through its user-focused '5G First' strategy, it provides a customer-first 5G network that offers not only speed superiority but also ultra-low latency and battery saving effects.

When discussing the maximum speed of a 5G device, LTE speeds are sometimes added. In this case, while there is an advantage in that the maximum speed is increased by adding LTE speeds, a counterproductive effect occurs where the ultra-low latency performance described as a key characteristic of 5G cannot be expected because the total latency is leveled down by reflecting LTE latency.

In mobile communication, the maximum speed provided by a single base station is shared among all subscribers served by that base station. Therefore, considering that the number of 5G subscribers will be smaller than that of LTE in the early stages of 5G service, it is judged that the speed improvement expected when combining LTE, which already accommodates a large number of subscribers, with 5G will be minimal. KT provides a 5G network based on the '5G First' strategy to complement these limitations and provide the best 5G services to customers.

KT's '5G First' strategy prioritizes the allocation of 5G base station resources to enable customers to experience the maximum performance of 5G. This not only enables the provision of services that fully utilize 5G's ultra-low latency but also reduces battery consumption on customer devices by approximately 25%. KT announced that it achieved a maximum transmission speed of 1Gbps in actual field environments using Samsung Electronics' 3.5GHz commercial base station and the Galaxy S10.
"We will install 30,000 base stations nationwide by the 5th of next month, when we begin recruiting 5G subscribers," said Seo Chang-seok, Executive Vice President and Head of KT's Network Strategy Division. "Half of them, 15,000, will be installed in Seoul, and Chinese Huawei products will not be included."


Improved perceived quality with ultra-low latency 5G networks at edge communication centers
In conventional mobile communications, user-perceived quality has generally been improved by increasing bandwidth and reducing 'transmission latency'. However, as there are limitations to improving perceived quality through increased bandwidth, 5G focused on reducing transmission latency.

For example, when loading a webpage that requires receiving about 3MB of data, the process actually requires repeating transmission and reception about 100 times, and the transmission delay time occurring between these transmission and reception processes determines the overall webpage loading time. Minimizing such transmission delay time on the network can significantly improve the user experience quality.

KT has established '5G Edge Communication Centers' in eight locations nationwide by applying Edge Computing technology, which can reduce transmission latency, in order to provide 5G services with maximized ultra-low latency characteristics and improve user-perceived quality.

KT has reduced the existing transmission latency of 18ms to 10ms by having users process data traffic at the nearest adjacent edge communication center. A transmission latency of 10ms is expected to significantly aid the activation of VR media. This is because VR content must be transmitted with a latency of 16.67ms or less to allow users to enjoy it continuously.


Providing 5G networks for customers with battery saving technology
From a user's perspective, the biggest concern when using a smartphone is battery drain. To address this concern, KT announced that it has introduced the world's first 'battery saving technology (C-DRX)' to its 5G network. KT already introduced C-DRX to its nationwide LTE network in 2017.
"Going forward, we will provide the highest quality 5G services to our customers and realize customer satisfaction through people-centered technology," said Seo Chang-seok, Executive Vice President and Head of KT Network Strategy Division.


Advanced network control technology based on 5G
KT has applied new security technologies to 5G to ensure that individuals and businesses can receive secure communication and services. The newly introduced security technologies are GiGA Stealth and Network Slicing, which were also mentioned at MWC19.

It was explained that Giga Stealth is a security technology that makes the IP of IoT itself invisible, and Network Slicing is a service that guarantees security and quality through network separation suitable for the characteristics of each service and terminal, and will be applied to enterprise-dedicated 5G in the future.

KT offers ▲Dr. Wais (AI SON), an AI-based self-recovery technology, and ▲Dr. Wais, a technology that analyzes and prevents the root causes of network failures, such as line failures and accidents, based on big data. Lauren also introduced AI-powered technologies, such as OPERA, a technology that supports configuring the entire network to suit the customer's specific needs.

Along with this, technologies were also announced, including: ▲ holograms that provide the exact size of the other party on the screen, transcending spatial and temporal limitations; ▲ GiGA Twin, an intelligent remote control platform that can be quickly and easily applied to various domains such as energy, bridge safety, and buildings; ▲ Edge CDN, which enables seamless transmission of large-capacity data and real-time sharing with ultra-low latency; and ▲ 'precision positioning,' which provides location information essential for sophisticated autonomous driving in real-time with ultra-low latency.
Lee Seon-woo, Senior Vice President and Head of the Infra Research Institute at KT Convergence Technology Institute, said, “We developed an in-building coverage repeater through the Open Lab,” adding, “Our goal is to build 1,000 partner companies by 2020 to develop and verify technology together with various partners.”

KT opened the '5G Open Lab' on September 4 of last year to promote 5G commercialization and ecosystem activation, marking 555 days since the declaration of 5G commercialization.