Every major technological revolution will promote a qualitative leap in human society. Today, the world is entering the era of the fourth industrial revolution, and the internet of things (IoT), digitalization and intelligence have become the characteristics of this era. The existing wired networks, Wi-Fi, 3G, 4G and traditional private enterprise networks have been unable to adapt to the digital change and upgrade of vertical industries in the new era because of their own limitations. However, 5G can better meet the needs of digital upgrade for its high bandwidth, low latency, massive connections, combined with cut-edge technologies like network slicing, AI, big data, edge computing, and cloud computing platform. Compared with individual services, industry applications have special requirements for ultra-low latency, high reliability, and high security, so it is necessary to build 5G private networks to meet the applications of various industries. The end-to-end 5G private network planning is also an important part of mid- and long- term 5G planning.
Flexible 5G Private Networks for Differentiated Industry Applications
A major technological innovation in 5G networks is to achieve end-to-end network slicing, which can divide a 5G physical network into multiple virtual networks to provide special services for thousands of industries. Therefore, 5G private network planning is first of all based on the public network. The following four 5G private network models can be planned to flexibly adapt to application scenarios of different industries and specific customers (Fig. 1).
—5G private line:
A 5G private line from core network to RAN completely shares the 5G public network and provides private line services for enterprises through QoS and APN. This mode is suitable for small and micro enterprises and can be implemented in both NSA and SA modes.
—5G virtual private network:
The 5G public network is completely shared by a 5G virtual private network, which provides private network coverage for enterprises through end-to-end slicing. This mode is applicable to small and medium-sized enterprises.
—5G hybrid private network:
In a 5G hybrid private network, MEC and UPF are separately deployed for the enterprise, so that local data traffic can be offloaded in the enterprise campus. This mode is applied for large and medium-sized enterprises.
—5G physical private network:
A separate 5G physical private network is built for a super-large enterprise, which consists of 5GC, MEC, transport and radio wireless base stations. The general application scenarios include large ports and mines.
E2E 5G Private Network Planning Based on Public Network
End-to-end (E2E) 5G private network planning solution consists of service platform, core network, MEC, RAN, transport network, and terminals. The basic idea of 5G private network planning is based on the public network, combined with private application characteristics and special scheme considerations.
—Service platform: Compared with the public network only for individual consumer services, the service platform is a new and independent platform that provides vertical industry services based on network connections, including infrastructure as a service (IaaS), general platform as a service (GPaaS), application platform as a service (APaaS) and software as a service (SaaS).
—Core network: From the whole network perspective, whether 2C and 2B core network platforms are co-built or built independently is a key strategy of operators, which needs to be determined based on their strategic positioning of the 2B market and their business development. The use of lightweight 5GC for specific private users can meet the needs of independent deployment of low-cost core networks. The dedicated UPF can also be deployed close to different application nodes according to service needs.
—MEC: MEC is an industry-oriented edge cloud solution that can be deployed at network access nodes, aggregation nodes, or even core nodes to meet the flexible needs of industry users for latency, bandwidth and security. It is one of the most important platforms in 5G industry applications.
—RAN: In terms of networking, RAN basically shares the public network. It should be noted that private networks often have a large demand for indoor coverage and 5G indoor cell planning is the focus.
—Transport network: The private network basically shares transport network with the public network, but provides higher-level services for industry applications through slicing.
—Terminals: Industry terminals are also an important factor affecting 5G private network planning. At present, the terminals in line with the industry application are CPEs and some industrial modules, which will be gradually enriched in the future.
Key Technology and Function Planning for Precise Empowerment
Industry applications have higher performance requirements than ordinary individual services. In addition to targeted end-to-end network planning, 5G private networks need to introduce key technologies and functions for industry applications and precise enablement. The following key functions and technical solutions will be introduced on demand in the deployment of 5G private networks.
—E2E network slicing: In the management domain, the end-to-end slice orchestration and management system implements slice design, slice establishment, and slice deletion. In the operation domain, end-to-end network resources are guaranteed through the NE slicing technology, such as QoS+5QI at the RAN side, FlexE in the bear network, and micro-service and NFV orchestration in the core network.
—Bandwidth guarantee and uplink enhancement: In addition to ultra-broad bandwidth provided by M-MIMO, physical resource blocks (PRBs) are reserved to guarantee the bandwidth for industry applications. The industry applications have high requirements for uplink services. TDD+FDD dual aggregation is an important technology for uplink enhancement.
—Low latency and low jitter: 5G private networks reduce end-to-end network latency through MEC architecture and new air interface technologies. FlexE and TSN are also the solutions to reduce latency and jitter.
—Precise positioning: High-precision positioning is a common requirement in industry applications. The main technologies to implement high-precision positioning include 3GPP-based AoA+RTT and Multi-RTT, and non-3GPP based Bluetooth5.1 and UWB. 3GPP R16 further enhances high-precision positioning.
—High reliability: Link protection is implemented for high reliability, including dual-card terminals, dual connectivity, and dual backhaul. Optimized coding rate and retransmission can also improve reliability.
—High security: High security of private networks can be achieved through end-to-end network isolation, local offload in data parks, and access control and management.
5G Private Network Planning for Typical Scenarios
Although the needs of industry users are different, 5G private network planning in the same industry scenario has something in common. The planning for 5G private networks in three typical industry scenarios is recommended as a reference.
—Smart factory: 5G hybrid private network is planned for large and medium-sized industrial enterprises, where a dedicated MEC is deployed in the industrial park, 5G AAUs are used for outdoor coverage, and QCells are used for indoor coverage. Main services of the smart factory include cloud AGV, remote control, machine vision, HD video monitoring and automatic driving. These services fall into three types: uRLLC, eMBB and mMTC. Accordingly, three end-to-end network slices are designed, with data offloaded in the park through MEC.
—Smart grid: The grid usually involves super-large enterprises, whose services are scattered in space. Therefore, 5G hybrid private network is planned, where multiple MECs are deployed in the regional and headquarters data centers respectively, and 5G RAN and 5GC are shared with the public network. Main services of the smart grid include differential protection of distribution network, phasor measurement unit (PMU), electric load response, precise load control, HD video monitoring and unmanned aerial vehicle (UAV) inspection. As the uRLLC slice of the grid has high requirements for delay and jitter, it is necessary to introduce PRB reservation and TSN solutions to ensure service performance.
—Smart port: 5G physical private network is planned for a super-large port that has large-scale independent parks, large needs for digital services, and high requirements for service security. Dedicated 5GC, MEC and wireless sites are deployed for the port. Main services of the smart port include real-time customs inspection, remote crane control, HD video monitoring, automatic driving and personal communications. Slices are planned according to different services in the physical private network. Internal data traffic of the port area is bypassed to the data center through MEC, while its external traffic is connected to the public network through the private 5GC.
Enabling various industries is the greatest value of 5G applications, but it must be implemented based on a powerful network. ZTE has gained a lot of practical experience in 5G industrial applications and can provide operators with tailor-made 5G network planning for the 2B market.