SK Telecom Builds AI Infrastructure Momentum with GPUaaS and the Haein Cluster

The growing demand for artificial intelligence computing is reshaping the role of telecommunications operators. As AI models become larger and more computationally intensive, the need for high performance infrastructure has moved into sharp focus. In response, SK Telecom is positioning itself not only as a connectivity provider but also as a key supplier of AI infrastructure through its GPU-as-a-Service offering.

At the centre of this strategy is the Haein GPU cluster, one of the largest AI computing platforms in South Korea. Built around more than 1,000 GPUs from NVIDIA based on the Blackwell architecture, the platform provides the computing power required for large scale AI training and inference workloads. The cluster represents a significant step forward from the earlier infrastructure based on NVIDIA H100 GPUs and forms part of SK Telecom’s wider sovereign AI infrastructure initiative.

The Haein cluster is hosted within the company’s Gasan AI Data Center in Seoul and is designed to deliver high performance computing capacity at national scale. The system supports intensive AI workloads including the training of large language models while also providing the flexibility required for enterprises and research organisations developing their own AI applications. The platform’s architecture allows large GPU resources to be combined into a single cluster while still being dynamically allocated to different users depending on demand.

A key component enabling this flexibility is SK Telecom’s proprietary virtualisation platform known as Petasus AI Cloud. The software layer allows the large GPU cluster to be partitioned and reconfigured dynamically, enabling customers to access the exact amount of computing power they require. This capability is essential for GPU-as-a-Service platforms where workloads can vary significantly, from small development environments to large scale model training that requires hundreds of GPUs operating simultaneously.

Alongside this, the company provides operational management through its AI Cloud Manager platform. This AIOps based environment supports the full lifecycle of AI services including development, training, deployment and operational monitoring. By combining infrastructure with operational tooling, SK Telecom aims to provide a more integrated AI computing platform rather than simply raw GPU capacity.

The Haein cluster also plays an important role in South Korea’s national AI strategy. The platform has been selected to support a programme led by the Ministry of Science and ICT that focuses on strengthening the country’s AI computing infrastructure and enabling the development of competitive national AI foundation models. Through this initiative, the cluster will contribute computing resources to projects developing sovereign AI capabilities tailored to the Korean language and domestic industries.

The name of the cluster itself reflects this national perspective. Haein takes inspiration from Haeinsa Temple, which houses the historic Tripitaka Koreana, a vast collection of Buddhist scriptures recognised as a UNESCO World Heritage archive. The naming reflects the ambition to create a modern repository of digital intelligence, supporting the development of AI knowledge and capabilities within the country.

Delivering infrastructure at this scale requires a broad ecosystem of partners. SK Telecom has worked with companies including Supermicro and Penguin Solutions to design and deploy the server infrastructure and integrated AI data centre solutions required for the cluster. These collaborations enable the rapid deployment of high density GPU servers and the supporting cooling, power and networking systems necessary to run large scale AI workloads.

The industry has already taken notice of the platform. The Haein GPU cluster was recognised at the MWC Barcelona 2026, where SK Telecom received the Best Cloud Solution award at the GSMA Global Mobile Awards. The recognition reflects the company’s continued progress in cloud and AI infrastructure development and marks the third consecutive year that its cloud related technologies have been acknowledged in this category.

For telecoms infrastructure professionals, SK Telecom’s GPU-as-a-Service strategy illustrates how operators are expanding beyond traditional connectivity services. By building large scale AI computing platforms inside their data centre footprint, operators can leverage existing strengths in infrastructure, power management and network integration to participate in the rapidly growing AI economy.

As AI adoption accelerates across industries, the demand for scalable computing infrastructure will continue to grow. With platforms such as the Haein cluster and its GPUaaS offering, SK Telecom is positioning its network and data centre assets as part of the core infrastructure supporting the next generation of AI innovation.

Related Posts: 

• Telecoms Infrastructure Blog: SK Telecom's Vision for Future Telco Infrastructure in the AI Era
• Operator Watch Blog: SK Telecom on 'Applying AI to Transform Customer Experience'
• Free 6G Training - SK Telecom 6G White Paper: View on Future AI Telco Infrastructure
• Free 6G Training: SK Telecom Releases 6G White Paper Looking at Lessons Learned in 5G and Way Forward with 6G
• Free 6G Training: SK Telecom Claims ‘Bare Metal-Based Cloud-Native 5G Core’ as Foundation for 6G Evolution
• Telecoms Infrastructure Blog: SK Telecom’s 5G MEC Status and Plan 

Seoul Metro Wi-Fi Backhauled by Samsung's 5G mmWave Network Solution

In our earlier posts we talked about how Wi-Fi 6 is being promoted by South Korea's ministry and also how mmWave has not been very successful in Korea. Having said that, earlier last year, Samsung Electronics announced that it has signed contracts with all three South Korean operators to supply its 5G mmWave network solutions and boost connectivity for passengers on the Seoul subway system:

Over 3.6 million passengers use the Seoul subway daily across over 300 stations. With a population of 9.6 million, Seoul is one of the world’s most densely populated cities, with its subway serving as one of the major means of public transportation for the busy metropolitan area. The subway system is expansive, resembling a spider web network that connects Seoul and the surrounding areas, carrying over 30 percent of the city’s population.

While the Seoul subway system has already been providing stable 5G (3.5GHz), 4G and Wi-Fi services, mobile data demands in subways continue to rise exponentially as Korea’s monthly average 5G data consumption reaches approximately 25GB per person.

.@Samsung is supplying #5G #mmWave equipment to Korean🇰🇷 #MNOs @SKtelecom, @kt_corp and @LGUplus powering Seoul Metro connectivity across ~300 stations🚆. This partnership will enable ultra-high data speeds for over 3.6M daily passengers. https://t.co/KZSGeWuMeF pic.twitter.com/hkGK7sAhl1

— Samsung Networks (@SamsungNetworks) May 1, 2022

Later this year, Samsung’s 5G mmWave solutions will enable the subway’s Wi-Fi services to meet increasing data demands by leveraging mmWave’s wide bandwidth, extensive capacity and massive throughput. Subway passengers will be able to enjoy bandwidth-intensive applications such as high-speed, superior-quality streaming for live sports games, movies, mobile games and video communications. These will be delivered at Wi-Fi speeds up to ten times faster on average than currently provided.

In addition to transforming the daily mobile experience for subway users, Samsung’s advanced 5G mmWave solutions will drive a diversified range of use cases and business opportunities for new entrepreneurs, app development startups and consumers. Utilizing mmWave bandwidth can not only bring to life next-generation services such as the metaverse, cloud gaming and Extended Reality (XR) remote learning, but it can also be expanded beyond transportation to industries like retail, medicine, media and entertainment.

A key component of the Seoul subway commercial deployment is Samsung’s mmWave 5G radio solution, Compact Macro, which brings together a baseband unit, radio and antenna in a single form factor. Optimized for mmWave 5G, it uses in-house modems, radio frequency integrated circuits (RFICs) and digital analog front end (DAFE) ASICs.

Complete press release here. Embedded below is a short promo video on this

Related Posts: 

• Telecoms Infrastructure Blog: London Underground Mobile Network Infrastructure
• Telecoms Infrastructure Blog: Bringing Connectivity to Underground Rail Network
• Connectivity Technology Blog: Deutsche Bahn to get Seamless Mobile Network Along all Tracks
• Connectivity Technology Blog: China Unicom Brings 5G Connectivity to Nanjing Metro
• Connectivity Technology Blog: Paris Metro is now 100% covered with LTE
• Operator Watch Blog: Wi-Fi and 5G Status in South Korea
• Operator Watch Blog: South Korea's Ministry promotes Wi-Fi 6, says WiFi is like 5G
• Operator Watch Blog: Is South Korea Losing its 5G Crown?
• Free 6G Training: Samsung talks about 6G Progress and Demos
• Free 6G Training: Samsung's 6G Spectrum Whitepaper Discusses Candidate Bands 

Samsung's 3GPP-Compliant PS-LTE Network

After having been discussed for years by others, Samsung finally announced back in April that they are powering the world’s first 3GPP-compliant nationwide public safety LTE (PS-LTE) network in Korea, in collaboration with leading mobile operators.

A press release from them said:

This PS-LTE network, operating in the 700MHz spectrum, offers fast and reliable connectivity to first responders in over 330 public safety organizations and agencies, including police, firefighters, emergency medical services and the military.

The deployment includes Samsung’s Mission-Critical Push-to-Talk (MCPTT) with multimedia broadcast capabilities, known as evolved Multimedia Broadcast Multicast Service (eMBMS). This enables simultaneous transmission to up to 2,500 user devices per cell, which is more than twice the volume of devices supported by previous generation technologies.

In this buildout, the PS-LTE network was also interconnected with the existing LTE-Maritime (LTE-M) and LTE-Railway (LTE-R) networks that were already operating in the 700MHz spectrum.

With nationwide coverage, the network serves as a unified platform that helps ensure interoperability among various public safety institutions. This delivers real-time accessibility and enhanced communications capabilities among public safety agencies and personnel in emergency situations.

Years after talking about eMBMS, it's still alive and kicking.

Meet the world's first 3GPP-Compliant Nationwide Public Safety(PS) Network with MCPTT Service & eMBMS in Korea powered by @SamsungNetworks

PS-LTE network @ 700MHz band for 300+ PS orgs.https://t.co/Io6q86ZGfl pic.twitter.com/impMwTnKGW

— Neil Shah (@neiltwitz) April 26, 2021

They also released an Infographic and a Whitepaper.

In a recent Networks Techtalk, Timothy Paul discussed Samsung’s latest end-to-end MCPTX solutions that provide powerful data and video communications capabilities designed for first responders and public safety officials. The video of that is embedded below:

Related Posts:

• Connectivity Technology Blog: Kima - Faroese Telecom's Mission Critical Communications Solution
• Connectivity Technology Blog: Virve 2.0 is becoming a broad-band service
• The 3G4G Blog: Virve 2.0 - Finland's 4G/5G Public Safety Network
• Connectivity Technology Blog: Verizon and Nokia Put Small Cell in the Air at #OCR2019
• Connectivity Technology Blog: Air-to-Ground (A2G) Network for Emergency Communications
• The 3G4G Blog: 5G Private and Non-Public Network (NPN)
• The 3G4G Blog: Update from 3GPP on LTE & 5G Mission Critical Communications
• The 3G4G Blog: Update on UK's Emergency Services Network (ESN) from #BAPCO2019
• The 3G4G Blog: A practical use of MOCN in ESN
• Telecoms Infrastructure Blog: Meshing for BYOC (Bring Your Own Coverage) 

SK Telecom’s 5G MEC Status and Plan

 

Back in December, at '5G Connected Edge Cloud for Industry 4.0 Transformation – 2020 Spotlight Series', Kang-Won Lee, Vice President, 5GX Cloud Labs, SK Telecom gave a talk on SK Telecom’s 5G MEC Status and Plan. 

It was interesting to see that while the industry has changed the definition of MEC to Multi-access Edge Computing, SKT still refers to it as Mobile Edge Cloud. As SKT has now crossed over 10 million 5G subscribers, they have noticed a lot of demand for Edge compute capability. While there is a demand, enterprises, factories, buildings, etc. are not interested in managing their own infrastructure. They would rather somebody else provides the services. This is where SK Telecom sees new business opportunities in the future. Along with the high throughput, high capacity and low latency, security and privacy is very important as well. 

As the services move to edge, there is more predictibility on QoE and the latecny can be reduced to as low as 1ms which is a huge benefit to critical applications. While they are not there yet, they are moving towards that goal. There is also a huge opportunity for public cloud providers here.

SKT has 2 main deployment models as can be seen. The public edge where they have data centres distributed throughout the country and can hence provide MEC services to 5G users nationwide. On the other hand, On-site edge is useful for providing private MEC services to enterprise and government users. Ideal for smart factories, smart hospitals, offices, etc. In both cases, SKT are open to collaborate with the users, communities, open source, big companies, etc.

Finally, SKT MEC Architecture can be seen in the picture above. The 5G network and 5G-MEC gateway can be seen which is connected with the compute and storage resources which are in turn connected to SKT tech assets or other operator platform or public cloud platform as required. The video provides more details including the SKT MEC Architecture details.

The slides are available to the registered users here and the talk is embedded as follows:

Related Posts:

• Telecoms Infrastructure Blog: Operator Cloud Infrastructure and Innovation Strategy
• Telecoms Infrastructure Blog: Docomo 5G Open Innovation Cloud
• Telecoms Infrastructure Blog: Rakuten details how Cloud will make Telecommunications Industry Irrelevant
• Telecoms Infrastructure Blog: Edge Computing and the Future of Small Cell Networks
• The 3G4G Blog: 5G Private and Non-Public Network (NPN)
• Telecoms Infrastructure Blog: SK Telecom's In-building 5G NR Repeaters and 'Layer Splitter'
• Operator Watch Blog: SK Telecom's 5G Strategy and Services
• Operator Watch Blog: 5G+ Strategy of the Republic of Korea 

5G Infrastructure in South Korea

The three South Korean operators made a history when they all launched 5G network simultaneously, thereby making South Korea the first country with all operators having launched 5G.

Samsung's big break in 5G came with them being selected by all the three operators for their 5G networks. Now they have written a three part blog and a whitepaper to highlight the progress of 5G in Korea. Links as follows:

• Key Drivers for Korea's 5G Success (Part One)
• Key Drivers for Korea's 5G Success (Part Two)
• Key Drivers for Korea's 5G Success (Part Three)
• White Paper: Optimized 5G Solutions that deliver on the Promise of 5G

Even with all the progress, it is not a smooth sailing for 5G in S. Korea. A recent report in the newspaper Korea Herald said that More than half a million 5G network users returned to 4G. The article explained:

The figure -- 562,656 users who downgraded from their 5G subscriptions -- accounts for 6.5 percent of the total 5G network subscribers in South Korea, according to the report by Rep. Hong Jung-min, who belongs to the Science, ICT, Broadcasting and Communications Committee at the National Assembly.

The number of 5G network users as of end-August was 8.65 million in South Korea.

The lawmaker pointed out in the report released in time for the Assembly audit that many 5G users have gone back to the lower-speed network service as the high-priced new network system failed to offer quality connection and coverage.

Losing 6% of recruited 5G subs to 4G plans during 18 months is not a catastrophe when the annual mobile churn in South Korea is about 15%. But the lack of low-cost 5G plans is cited as a reason. KT took the first step and SK and U+ are now said to follow. https://t.co/NrYPlb0URL https://t.co/JOPSuxBoZC

— tefficient 🚥 (@tefficient) October 13, 2020

Here is a video from Samsung showing the Snapshot of Korea 5G

Related Posts:

• Telecoms Infrastructure Blog: Samsung's 5G NR Integrated Radio for mmWave spectrum
• Operator Watch Blog: All three mobile network operators in South Korea launched 5G on Dec 1, 2018
• Operator Watch Blog: Current IMT Spectrum Allocation in South Korea
• Operator Watch Blog: SK Telecom's 5G Strategy and Services
• Operator Watch Blog: How is KT Reducing the Latency of their 5G Network
• Operator Watch Blog: 5G+ Strategy of the Republic of Korea
• Operator Watch Blog: LG Uplus Tests 5G in 28GHz band using 800MHz Bandwidth. Sees AR as 5G Killer App
• Operator Watch Blog: How many 5G Cell Towers & Base Stations Worldwide? 

SK Telecom's In-building 5G NR Repeaters and 'Layer Splitter'

In-building coverage is the new battleground in South Korea. According to this report by Korea Times back in August

SK Telecom, KT and LG Uplus, which have been in cutthroat competition to improve the quality of their fifth-generation (5G) network services, are now in a race to boost 5G data speeds inside buildings.

Their move comes amid growing complaints over disappointing 5G network coverage since the next-generation mobile network services were launched in early April.

SK Telecom said Wednesday it has completed the development of the "5GX In-building Solution" that is capable of doubling the speed of 5G data transfer inside buildings and effectively dispersing data traffic to prevent overload on base stations in crowded areas such as shopping malls and subway stations.

The nation's top mobile carrier said the new technology will be applied to its commercial 5G networks after the third quarter of the year.

"We expect 80 percent of data traffic to be from inside buildings in the 5G era," said Park Jong-kwan, who heads 5GX Labs at SK Telecom. "We will continue to give efforts to provide users with seamless, high-quality 5G services inside buildings and in crowded areas."

The company said its new system features "Active Antenna" technology that allows 5G small cells, which refer to small indoor base stations, to be equipped with eight transmission and reception antennas.

This will double the speed of 5G data transfer as existing indoor base stations are capable of operating four transmission and reception antennas.

KT has also been working hard to expand 5G coverage inside buildings.

In May, the nation's largest broadband service provider and second-largest mobile carrier interlocked 5G repeaters with commercial 5G networks in cooperation with small and medium business partners.

Installed inside buildings where radio waves from base stations can hardly reach, the device helps improve the quality of 5G services.

KT is in charge of expanding 5G coverage in 95 large buildings out of 119 nationwide, such as airports and KTX stations, in a joint project by the three mobile carriers.

LG Uplus, the smallest player, also has been active in installing repeaters in small and medium buildings and underground parking lots to expand 5G coverage.

The company is planning to expand the application of beam-forming and multi-user MIMO (multiple-input and multiple-output) technologies to its 5G networks nationwide.

Back in May, SK Telecom won SCF Small Cell Awards 2019 in the category of “Commercial Small Cell Design and Technology” for commercializing the world’s first 5G NR RF repeater. According to the press release:

SK Telecom won this year’s SCF Small Cell Awards for developing and commercializing, for the first time in the world, two different types of 5G NR RF repeaters operating in the 3.5GHz band in 2018. 5G RF repeaters, which amplify 5G radio signals to allow them to travel greater distances, are used to enhance 5G service quality by improving coverage for in-building areas.

SK Telecom’s RF repeater is built with 5G NR standard-based Time Division Duplex (TDD) Synchronization detection technology, which enables a more efficient use of limited frequency resources. In addition, the 5G repeater provides wide bandwidth support and operational optimization features.

Going back to the Small Cells World back in May, SK Telecom presented their solution but the presentation was not shared. Here are some relevant pictures from their presentation:

SK Telecom: will use various inbuilding solutions to complete 5G network. e.g. A 3.5GHz RF repeater to extend home/small building coverage - running remote antennas from the repeater.

— TheMobileNetwork (@TMNmag) May 21, 2019

Source: Phil Kendall

As can be seen in the picture (click to enlarge), depending on the use case and location, the InBuilding solution would change from Small cells to AAU and Repeaters.

Source: Dean Bubley

As you can see in the picture above, the 3.5/28 GHz layer split solution improves capacity of the building by creating multiple layers to improve the capacity. There is a new press release on this topic, which is covered in the post later on.

Source: Dean Bubley

The Speed Repeater above and the RF Repeater below is backhauling on the existing macro, similar to the In-band backhauling (IBBH) I have described earlier or Sprint/Airspan MagicBox.

Source: Dean Bubley

In a recent press release, SK Telecom announced that they have expanded the 'Layer Splitter', a dedicated equipment for 5G inbuildings, to 1,000 buildings, starting with WeWork Seolleung Branch (Gangnam-gu, Seoul). SK Telecom customers will be able to use 5G services twice as fast as existing in-building equipment in major domestic buildings such as shopping malls and department stores.

'Layer Splitter' is the equipment based on '5GX In-building Solution' developed by SK Telecom in the world in August. If existing indoor equipment is equipped with two antennas for data transmission and reception, 'Layer Splitter' is a four-integrated antenna equipment that can process more data simultaneously in the same frequency band.

It also integrates several signal conversion devices * that go through for communications services. The integrated device is half the size of the device as before, and data transfer rates are faster with fewer signal conversion steps. In addition, the integrated device is placed forward in the base station and only the antenna is installed inside the building, enabling quick action in the event of a problem without visiting the building.

※ Previously, it had to go through four-step signal conversion (digital signal → optical signal → base signal (IF) → optical signal → wireless signal (RF)), but 'layer splitter' Combined 'matcher' and 'donor', a device that converts the base signal (IF) into an optical signal

SK Telecom plans to expand in-building coverage centered on 'layer splitters' in buildings with a large number of floating populations such as large shopping malls and department stores. 

Wework, the first construction site, is a shared office where several ICT-related companies collaborate and expect various business models based on Korea's best 5G infrastructure. In particular, SK Telecom and Wework have been working together since last year's strategic partnership, including building 5G infrastructure.

Chang-Kwon Chung, head of infrastructure engineering group at SK Telecom, said, SKT customers can experience differentiated communication quality with the only equipment dedicated to 5G in-building. “In-building will be able to efficiently accommodate in-building traffic that will continue to increase in the 5G era. "We will continue to advance our proprietary solutions."

Hopefully we will learn more about this solution in near future.


Related Posts:

• SK Telecom's 5G Strategy and Services
• 5G+ Strategy of the Republic of Korea 

ETRI working on Small Cell Base Station in a Backpack and 5G Indoor Femtocells

Came across this slightly old news in March issue of ETRI Webzine:

Following the development of the LTE small-cell base station SW in 2016, ETRI announced on February 7 that it successfully developed a SW supporting LTE-TDD dual connectivity.

These technologies are evaluated as core technologies for future 5G communication through upgrading of conventional SW technologies, since they may be applied to buildings, stadiums, and homes.

The technologies are suitable for the locations where the traffic is rapidly increased, such as stadiums, department stores, disaster-stricken areas, and military camps. The small cells may be attached, like a wireless LAN AP, to walls inside and outside buildings, utility poles, and communication antennas, or may be carried in the form of a backpack. The research team explained that the size of the small-cell was minimized as the size of a wireless LAN AP for indoor purposes and as the size of a shoe box for outdoor purposes. The small-cell backpack weighs about 10 kg.

These accomplishments will remove the communication shadows and blind spots between cells, and will help to develop independent technologies by replacing the conventional products from other countries.

In a more recent news on this topic (September 2018):

Following the successful localization of software for LTE Small Cell, which is used in the same manner as wireless access points operating within tens of meters to 1 km, while serving as a small base station, ETRI researchers began research to localize small cell equipment essential to establishing 5G infrastructure going forward. The focus of the research is on the development of technology capable of increasing the maximum transmission speed (eMBB), which is one of the most critical criteria for 5G technology, and especially the perceived transmission speed on the user side.

According to Yonhap News (translated by Google translate):

SK Telecom will be participating in 'Intelligent 5G Small Cell Technology Development Task' together with Korea Electronics and Telecommunications Research Institute (ETRI), domestic wireless communication equipment company Teltel and U Cast. The project is sponsored by the Ministry of Science, Technology and Information and is organized by ETRI.

In this project, SK Telecom sets up requirements for small cell system development. In addition, ETRI and equipment companies provide a test environment for small cell equipment verification. ETRI develops software, and Contela and Yu Cast develop hardware.

SK Telecom and other collaborative research groups plan to open API (application programming interface) to small cell. This reduces the burden of SMEs and start-ups to develop their own interfaces.

SK Telecom and ETRI are planning to develop international standard technology and secure original patents in the small cell field based on research results.

SK Telecom announced on February 23 that it will participate in 'Intelligent 5G Small Cell Technology Development Task' together with Korea Electronics and Telecommunications Research Institute (ETRI), Kontela and U Cast of domestic wireless communication equipment. A joint research team is taking a commemorative photo in front of the first workshop at Daejeon ETRI fusion technology research and production center. 2018.8.23

SK Telecom Park Jong-kwan, director of Network Technology, said, "In the 5G era, 80% of total traffic will occur indoors." "We will take the lead in 5G technology development so that customers can fully enjoy virtual reality and hologram services."

SK Telecom: Commercial deployment of LTE Femto cell

SK Telecom does not fail to impress with their aggressive roll-outs and impressive solutions to challenging problems. One such presentation from the Small Cells World Summit 2013 in London is embedded as follows:

Commercial deployment of lte femto cell with the innovative technologies and the roadmap from Zahid Ghadialy

Another presentation from late last year is available here.