2020 will see large-scale 5G deployment worldwide. According to the Global Mobile Suppliers Association (GSA), commercial 5G is now available in 38 countries. Its latest report also shows that there have been 92 commercial 5G networks in these countries by the end of July 2020. Meanwhile, leading operators in China, Japan, South Korea, America, and European countries have started to build up commercial 5G SA networks.

Multi-RAT Convergent Network Construction Is the Key to Commercial 5G Rollout

Operators are faced with solid top-of-mind challenges, for example, coexistence and interconnection of 5G and conventional networks, seamless user migration, and O&M of multiple networks, when they launch their commercial 5G networks. Failure to address these issues will certainly hinder the commercialization of 5G, as 5G network construction cannot be completed overnight. As GSMA Intelligence expects, 5G users will not exceed 15% of the total number of users, 4G users will account for about 57%, 3G users about 21%, and even 7% of users will still use 2G services by 2025. This data reveals once again that multi-RAT networks will coexist for a long time.

Figure 1: User proportions under different RATs by 2025

In this regard, operators are opting for a convergent 2G, 3G, 4G, and 5G core network that features the following:

• Capable: It shall be able to serve as many subscribers as possible, meeting the requirements for the first 5G subscribers that are growing rapidly.
• Agile: It shall allow fast network building and service rollout, seizing the competitive advantage to stay ahead of the market.
• Exceptional: In addition to delivering a supreme user experience in 5G coverage, it shall ensure a consistent service experience in areas without 5G coverage.
• Cost-efficient: Its adoption shall help avoid repeated investment and protects existing investment.

Fully Convergent Core Network Empowers 5G Business Success

To fulfill operator demands for building a full-capacity and cost-efficient network that delivers an excellent user experience and shortened TTM, Huawei has proposed the fully convergent 5G core network solution. While supporting both the 5G NSA and SA architectures, the convergent 5G core network is also compatible with 2G, 3G, and 4G networks.

Figure 2 Fully convergent vs separated

So what’s the secret of this full convergence?

First, Huawei’s 5G Core (5GC) adopts the microservice architecture. Microservices can be assembled like lego blocks for in-depth convergence. By doing so, only necessary modules are required and they get the least amount of resources required while providing the most functions with the best performance. This ensures the 5GC can always be able to accommodate a large number of subscribers.

Second, the 5GC fast tracks network construction and service rollout, as it allows smooth upgrade of the live networks and has little dependency on peripheral devices.

• Users on live networks can subscribe to 5G services without changing their (U)SIM cards or MSISDNs.
• Huawei’s 4G core network products have commercialized their distributed network architecture where the control planes are separated from the user planes and are fully meshed with one another. This architecture ensures that the CloudEPC can smoothly evolve to the 5G SA Core.
• The charging system, which may become a possible hurdle on the way of 5G commercialization because of it long, costly upgrade period and the fact that many vendors have not developed the SA-supported charging capabilities, now can be free from these issues. The Huawei's fully convergent core network can interconnect with the 4G charging system to charge 5G subscribers in addition to 2G, 3G and 4G subscribers, with just a few changes needed.

Third, the 5GC helps confine part of signaling exchange to internal modules rather than requiring inter-system communication when it comes to 4G and 5G interoperation. This means fewer control-plane handover messages and lower service latency, but improved handover success rate. In addition, the gateway and user-plane IP addresses remain unchanged during the handover, ensuring an uninterrupted service experience.

Last but not least, Huawei's fully convergent core network can effectively protect operators' investment.

• Cloud-based 4G devices on the live networks can be 5G-capable via a software upgrade, maximizing the return on 4G investment.
• Common 2G, 3G, 4G, and 5G modules can be shared, preventing the waste on hardware resources.
• The fully convergent 5GC enables operators to maintain only one core network, significantly improving their O&M efficiency.

In addition to leading the industry technological development, Huawei's fully convergent core network remains competitive in its best practices for commercial availability. There are operators from home and abroad who have launched their commercial 5G SA networks thanks to Huawei's fully convergent core network.

Looking into the future, Huawei will continue to help operators worldwide build a fully convergent 5G core network, laying a solid foundation for 5G business success.