5G Exploration: CDN and Edge Computing Practices and Challenges

Introduction – The Cloud+ Community Developer Conference (Beijing) concluded with the theme “5G Exploration: Core Technologies and Challenges”. Liao Long presented on how CDN technology and the industry are evolving under 5G and how they will shape the future.

1. The past decade: 98% of netizens have moved to mobile Internet

Reviewing the evolution from 2G, 3G to 4G, the speaker highlighted the rapid adoption curve: in 2009 only 60% of users accessed the Internet via mobile, while by 2018 almost all (98%) were mobile users.

With this massive shift, the question arises: what new challenges will 5G bring to these mobile users?

2. 2020 – The commercial year of 5G

The speaker noted that major Chinese cities rolled out 5G coverage in 2019‑2020, and encouraged the audience to test 5G signal availability on their devices.

Field tests in Shenzhen showed rapid base‑station deployment once operators committed to 5G.

3. Exploring CDN Edge Computing in 5G Scenarios

5G promises high bandwidth, low latency, and massive device connectivity. The speaker explained how moving computation from devices to CDN edge nodes can address latency and bandwidth constraints.

Case 1 – Live Edge Transcoding

By processing live streams at CDN edge nodes close to viewers, the system reduces bandwidth consumption and latency, especially for low‑viewership streams.

Case 2 – Smart Retail (优Mall)

Edge‑deployed devices can handle membership verification, heat‑map analytics, and other AI tasks without heavy on‑site hardware, enabling low‑cost, high‑performance retail solutions.

Case 3 – Dingdang Voice Assistant

By offloading speech‑to‑text and intent processing to CDN edge nodes, response time is cut by ~30%, achieving sub‑second interaction.

5G Scenario 2 – Low‑Latency Applications

The speaker described the multi‑layer latency in mobile networks and introduced MEC (Multi‑Access Edge Computing) as a way to push compute to the base‑station level.

Three detection approaches were discussed: app‑side probing, DNS‑level latency measurement, and fixed‑exit probing (the latter used by Tencent Video).

5G Scenario 3 – High‑Bandwidth Applications

With 5G’s large bandwidth, video quality (4K, higher frame rates) and traffic spikes during events (e.g., Double‑11) become critical challenges. Tencent built the “Volcano” burst‑resource system to dynamically allocate spare server capacity within seconds, avoiding massive over‑provisioning.

Containerization and rapid IP provisioning enable the system to add up to 1 TB of bandwidth within minutes.

4. 5G is Coming – Conclusion

The speaker emphasized that the presented practices are exploratory, encouraging the community to learn together.

5. Speaker Introduction

Liao Long, Tencent Cloud expert engineer, has been with Tencent since 2010, contributed to QQ Space, QQ Farm, and has led CDN R&D since 2014, focusing on edge computing, global acceleration, and security.