The Ministry of Industry and Information Technology recently announced the formulation of new industry standards.

It is worth noting that two "5G Inter-Network Roaming" standards - "General Technical Requirements for 5G Inter-Network Roaming Core Network Roaming" and "5G Inter-Network Roaming Core Network Roaming Test Methods" are listed.

This means that roaming on different networks is still "running fast". But will a breakthrough at the standards level open the door to a new world of internet roaming?

Roaming in different networks

In fact, there is not much time window left for roaming on different networks.

In 2020, the Ministry of Industry and Information Technology issued the relevant requirements of the "Implementation Opinions of the Ministry of Industry and Information Technology on Promoting Network Opening and Sharing to Promote 5G Inter-Network Roaming" (Ministry of Industry and Information Technology [2020] No. 117).

According to the plan, in 2021, we will promote the technical research on the implementation of the 5G inter-network roaming scheme, form relevant technical standards, formulate relevant test standards, complete the 5G inter-network roaming laboratory test, and organize and carry out the open-network pilot work. Before the end of 2022, basically build a 5G network covering urban and rural areas, with advanced technology, high quality, intensive, efficient, safe and reliable, and comprehensively promote 5G inter-network roaming.

In order to support the full achievement of this goal, the Ministry of Industry and Information Technology issued the "14th Five-Year Plan for the Development of the Information and Communication Industry" in November 2021, and required that 5G inter-network roaming test verification and equipment upgrades be accelerated to achieve county-level and below administrative areas. All 5G networks have the function of inter-network roaming. Basic telecommunications companies are encouraged to carry out inter-network roaming under a market-oriented mechanism, and provinces such as Tibet, Xinjiang, Inner Mongolia, Qinghai, Gansu, and Heilongjiang are supported to give priority to pilot projects of inter-network roaming.

This breakthrough at the standard level lays a solid foundation for the comprehensive promotion of 5G inter-network roaming at the end of this year.

The main drafters of the two aforementioned "5G inter-network roaming" standards are China Academy of Information and Communications Technology, China Telecom Group Co., Ltd., China Mobile Communications Group Co., Ltd., and China United Network Communications Group Co., Ltd. The three major operators will jointly formulate relevant industry technical standards and negotiate on important issues such as technical solutions for 5G inter-network roaming and settlement prices for inter-network roaming.

The future of roaming on different networks seems to be clearly visible.

Inter-network roaming is more "intensive and efficient"

What exactly is inter-network roaming? Why has the Ministry of Industry and Information Technology been vigorously promoting inter-network roaming?

Inter-network roaming, according to the popular explanation of Baidu Encyclopedia, means that the SIM card signed with a specific communication operator can also use the network of another communication operator. For example, the well-known international roaming is a kind of inter-network roaming. Users can use mobile communication services by accessing the networks of overseas operators. Therefore, many users have used inter-network roaming services.

From the perspective of roaming scenarios, there are mainly two types. One is that the home network party has no wireless signal in the roaming area, the visited network has 4G/5G signal, and the roaming user only uses the 5G network of the visited network. The other is that the home network has a 4G signal but no 5G signal in the roaming area, and the visited network has a 4G/5G signal, and the roaming user preferentially uses the visited 5G network.

Combined with the actual situation in China, the second roaming scenario is more in line with the actual needs of 5G co-construction and sharing in China. The reason is very simple. The 4G network coverage capabilities of the three domestic operators are almost the same; but the potential coverage capabilities of 5G are vastly different.

The original intention of inter-network roaming is also very obvious, because it is more "intensive and efficient".

The Ministry of Industry and Information Technology has pointed out that it is necessary to speed up the formation of a network pattern with multiple networks coexisting in hotspot areas and one network in remote areas, and create a 5G network with intensive resources and efficient operation.

Existing 5G networks are generally based on medium and high frequency bands and lack low frequencies below 1 GHz. The lack of low frequency means the lack of low-cost coverage; and if 5G really wants to increase the network utilization rate and the distribution ratio, it must enhance the coverage. However, spectrum resources are precious and scarce, and it is difficult for China Telecom and China Unicom to obtain enough spectrum resources for network construction in the short term. I just want to use the 700M 5G network of China Mobile-Broadcasting and Television by roaming in different networks.

In addition, 5G inter-network roaming can maximize the openness and sharing of networks, strengthen resource reuse, and improve the overall development efficiency of 5G networks. 5G inter-network roaming includes two technical routes: core network roaming and access network sharing. In the roaming area, roaming operators provide voice, data and short message services to users of this network and roaming users of other operators to ensure the same communication quality. .

How does roaming on different networks open the door to a new world?

The future of internet roaming is bright, but the road ahead is full of thorns.

Experts from China Unicom Research Institute once wrote that the implementation of 5G inter-network roaming at this stage still faces the following challenges:

First, there are no international precedents and international standards for reference. Equipment and terminal capabilities are immature, including SEPP equipment that is crucial to inter-network roaming networking, and there are no products available for testing. NSSF equipment does not support special slice mapping, etc. It is recommended to speed up technological research, standard formulation and testing and verification, and promote the establishment of various development and industrial chains.

Second, the problem of imbalance in the domestic telecommunications industry still exists. Under the conditions of unequal market share and network coverage, it is foreseeable that domestic basic operators will reach a consensus on the technical solution of 5G inter-network roaming and the settlement price of inter-network roaming. It is very unlikely that . It is recommended that the regulatory authorities take the lead in determining the technical route and interconnection plan, and formulate a unified settlement price for slow travel on different networks.

Today, these problems and difficulties are gradually being solved.

Previously, the three major operators had inconsistent attitudes towards inter-network roaming: China Telecom and China Unicom have been actively promoting 5G inter-network roaming; China Mobile (China Radio and Television) has an ambiguous attitude towards this. Now that the three operators can talk about a lot and jointly formulate 5G inter-network roaming standards, it is a big breakthrough.

Of course, this behavior has also been praised by many netizens in the home of the correspondent! Some netizens of the home of the correspondent pointed out that roaming between different networks has a negative incentive for operators. "You can't be proud of roaming, you must be ashamed of roaming. Only with such an idea can the overall progress of the coverage of both parties be promoted!" After all, for operators, high-quality differentiated development and good customer service are the keys.

However, some netizens also expressed some concerns: "Inter-network roaming is beneficial to the ITU in the short term, but it is not good for the ITU in the long run. Due to the market-oriented mechanism, the roaming fee for ITU users to the mobile network needs to be settled between networks, and the roaming fee should be higher than this network. After the user experience, the number portability will be gradually transferred to the network and become a permanent user of the mobile company. Due to the ability to bear the benefits, the network coverage in the rural areas will further shrink, resulting in a vicious circle and becoming a virtual operator.”

In fact, this is also the key to whether 5G inter-network roaming can truly be implemented. The establishment of a unified inter-network roaming settlement price is also the place where the decision-making wisdom of the supervision department is most tested. Only by doing this, can roaming on different networks truly open the door to a new world!