Reimagine the Mobile Network
The current, typical model for building a mobile network is outdated. Operators are constrained by vendor architectures that have remained essentially unchanged for more than 25 years. But the mobile industry and its supply chain are on the verge of a major transformation. This transformation is software-driven and will result in a more agile and efficient mobile network architecture. Any new end-to-end mobile network deployed today must adopt basic 5G system architecture principles even if it’s using LTE access. Operators should embrace the key principles that underpin the foundation of the 5G system architecture. The new cloud RAN architecture addresses the challenges of building multivendor networks and harmonizing to a common feature set.
Two ideas; one architecture
The new mobile architecture is built on two ideas. First, the principle of disaggregation, which is the notion that software can be purchased separately from hardware. And second, the principle of decomposition, which separates previously monolithic systems into multiple functions that can be deployed in the best way to meet operator business requirements, while using standard interfaces.
The idea of disaggregation, virtualization, and decomposition of various components and functions in the network and in the overall network architecture has opened many new exciting possibilities for operators. In the new and evolved end-to-end mobile architecture, the idea of disaggregation and decomposition is being applied in multiple ways with many advantages.
Disaggregation of hardware and software vs. monolithic appliance Cloud and virtualization technologies have enabled operators to disaggregate software from the underlying hardware. This model offers benefits such as:
● Agility and time to market for addition of new functions, features, or services.
● Wider and more open vendor ecosystem, enabling faster innovation and cost reduction.
● Rapid innovation in hardware and software with the ability to scale each independently.
● Potential to leverage common hardware, enabling repurposing and scale-out to support multiple applications. ● Ability to consolidate hardware Stock Keeping Units (SKU) from hundreds or thousands to less than 10.
Decomposition of functions with well-defined interfaces and splits
Functional decomposition allows even more flexibility beyond hardware and software disaggregation. The decomposition of the control and user plane for the evolved packet core is one example and the decomposition of radio functions into remote radio head/radio unit (RU), distributed unit (DU), and centralized unit (CU) is another. Decomposition makes it possible to:
● Place decomposed functions in optimal location types. For example, the user plane of evolved packet core can be placed closer to the user while the control plane remains centralized. This capability is a fundamental enabler of new architectures such as multiaccess edge computing.
● Scale each function independently, including control plane or user plane for evolved packet core or DU and CU for radio.
● Push user plane functions closer to the edge while keeping control functions more centralized to enable new capabilities with coordination and achieve better cost optimization.
● Foster a more open and multivendor ecosystem to drive faster innovation and lower costs.
The benefits of a cloud RAN architecture
Building a cloud radio access network (RAN) architecture has many benefits because it fundamentally changes the way networks are procured, built, and operated. Here are some of the benefits:
● Operational efficiency and reduction of truck rolls to the cell site by provisioning, commissioning, and managing services only with software.
● Agility, innovation velocity, and expedited time to service monetization while driving down the cost per user and the cost per unit of performance.
● Efficient partitioning of network functions and resources to support the 5G use cases such as enhanced mobile broadband, ultra reliable low-latency (URLLC), and Internet-of-Things (IoT) by using technologies such as software-defined networking, edge computing, service function chaining, and service orchestration.
● Pre-provisioning of baseband resources in a cloud RAN network isn’t required for the maximum capacity of the site. By factoring pooling gains, baseband resources are provisioned for the traffic profile of the entire network. These traffic profiles can be scaled up or down during peak-hour usage or in the case of high-traffic events.
● Scalability to quickly and cost effectively adapt to various network topologies and use cases.
● Enhanced network availability and reliability already built into network function virtualization (NFV) technologies such as OpenStack, the virtual infrastructure manager, and service orchestrator.
● Disaggregation of the hardware from the software using commercial-off-the-shelf, high processing density hardware, and open interfaces.
● Enablement of advanced algorithms such as cooperative multipoint and intersite carrier aggregation.
The future starts now. This new mobile network architecture can be realized today for 5GNR or LTE, and operators can choose a variety of paths to get there. Prudent steps will enable more agile service delivery with reduced expenses, resulting in increased competitiveness and profitability while providing a superior quality of experience. For more information about 5G and related topics, visit:
— Dan Kurschner, 5G and SP Mobility Marketing lead in Cisco Global Service Provider Marketing
— Susan Daffron, Technical Storyteller for Global Service Provider Marketing at Cisco