With the emergence of network softwarisation, open source software is going to become critical to 5G and play an important role in the development of 5G networks. Open source projects have a global developer community for solving technical challenges and expanding access to technical capabilities. The community model of open source development identifies and responds to user needs more rapidly than perhaps the traditional standards. Open source could help operators find interoperable solutions, encourage innovation, improve quality and security, and contribute to the community. The open source approach also helps vendors free up resources to pursue value-added products/services, improve quality and security, and contribute to the community.

the following aspects need to be considered when determining the applicability of open source across different layers of a 5G network…

5G infrastructure

In order to meet the bandwidth requirements of a  large number of devices, it is essential to transform the network so as to scale it up and make it agile while reducing cost. Network disaggregation with separation of user and control plane, separating the network operating system from the underlying hardware, and the use of general-purpose processing platforms is the key to creating networks that are massively scalable, agile and inexpensive.

Disaggregated hardware provides high performance at lower costs via approaches such as specialisation of tasks (for example, servers designed for packet processing) or conformance to a common standard for commoditisation.

5G radio network

5G brings a diverse set of requirements and use cases, and requires an entirely new Radio Access Networks (RAN) architecture that is flexible, modular and supports open interfaces. The new RAN architecture needs to be operationally efficient. It should be able to adapt to the diverse requirements of 5G.

5G core

The core network is a critical component, so it needs to be robust, highly resilient and high performing. 3GPP’s service-based architecture has standardised the network functions, their procedures and the inclusion of NF sub-modules. Standards also define the application program interface (APIs) to be used by providing data models, protocols and formats. However, a lot of innovation and research is happening in the open source community and by vendors so as to address specific problem areas or find new ways of implementing specific interfaces.

Management and control

Network function virtualisation (NFV) and software-defined network (SDN) are the key technologies required for improving the quality of service (QoS) with reduced capex, opex and energy consumption. RAN virtualisation is a key enabler for 5G, providing flexibility, scalability and most importantly optimum resource usage. Running software payloads on virtual machines provisioned on general-purpose processing platforms enables optimum usage of underlying network capacity and resources among deployments with varied traffic utilisation. Virtualisation benefits from low-cost, off-the-shelf hardware, while gaining greater agility in network management, service creation and provisioning.

The European Telecommunications Standards Institute  aims to address the challenge of moving away from proprietary hardware in NFV by converging the telco and IT networks. It applies standard IT virtualisation to consolidate network equipment types such as standard high-volume servers, switches and storage. NFV is complementary to SDN and can be easily used to manage NFV deployments.

Some of the areas to be considered as applicable for open source in the management and control domain are:

  • Orchestration of network services to provide expected agility in telecom networks requires a way to define these services down to their atomic nature, physical and virtual resources.
  • Network automation enables automation by programmatically configuring and provisioning network connections. With disaggregated software, separate control and user planes, and distributed network functions, there is a need to automate the means of managing the control of the NFV infrastructure and also the virtual network functions (VNFs) running on that infrastructure. This will transform the network by making it operationally efficient and reduce opex. The key to efficient network automation is maximum openness without which integration is not possible. In the absence of standard bodies that focus on network automation, there is a need for adopting an open source approach. Some initiatives in this area that should be considered as applicable for 5G are ONAP, ZSM (zero touch network and service management), and experiential network intelligence.
  • Analytics will also be important for network automation as it allows closed-loop feedback for effective service assurance. This will enable the network to self-heal, self-optimise and self-organise, bringing operational efficiency in network management. Open source communities have significantly contributed to big data analytics projects that utilise many open source stacks. With the growing number of devices and data explosion in 5G networks, real-time analytics of disparate data will be necessary.
  • DevOps is a software engineering culture and practice that aims at unifying software development and software operation. The cloud-native approach is fundamental to 5G network functions/services, and allows vendors and service providers to deploy DevOps methods to automate the process of building, validating and deploying workloads in NFV environments. This enables service agility. Any open source efforts in this DevOps area are applicable for 5G.
  • There are thousands of software and stress test tools, and a few hundred network test and simulation tools. By comparison, there are few such tools for testing telecom-specific protocols.

Convergence of telecom and IT with open source

Web-scale internet companies have adopted disaggregation, deploying thousands of white box servers and switches running modern operating systems, open source software and automation at an unprecedented scale. This has allowed them to transform traditional IT data centre infrastructure into a hyper-scalable architecture, enabling them to deploy services more efficiently and cost effectively.

Web-scale IT is characterised by the use of open source software and commodity hardware to create infrastructure that can be completely controlled by software. These cloud computing principles being adopted in technologies such as NFV and SDN will benefit the telecom industry in the 5G era. Web-scale architectures are already agile, born on the cloud and built on the new, faster principles that need to be adopted in order to build an agile mobile network. The web-scale delivery model is based on open source software, which supports continuous design, build, deploy and test. DevOps has made it possible for companies to develop infrastructure that responds quickly to change while remaining stable and reliable.

Open source software related to artificial intelligence, machine learning tools and real-time data ingestion developed by the IT industry will be applicable to the 5G world, where network automation will be critical for operational efficiency.

Unlike previous network generations, 5G is expected to support a diverse set of use cases and be agile in service delivery and efficient in network operations. Therefore, it is important to adopt the principles of web-scale internet companies. NFV, SDN and automation are key enablers of 5G. Hence, any open source project benefiting from the contribution of development done by web-scale companies should be considered as applicable.

Open source design

5G networks need to support diverse requirements and services. Thus, their design should support disaggregated network functions that are modular, flexible, and support extensible open interfaces and are cloud-native in all aspects. Open source must adopt and demonstrate these design principles in order to successfully integrate them into telecom infrastructure and applications. These should be important criteria while determining the applicability of certain open source projects for 5G.

Conclusion

Open source has been the key to recent advancements in high performance and flexible packet processing, which is important for 5G use case and services. There are already a number of open source projects that are well into their product cycles, and more will be emerging as 5G network deployments begin. Infrastructure management and control (automation, orchestration, analytics, testing) are the key areas that, if open sourced, could benefit mobile operators the most in their 5G deployments.

Operators have different strategies for evolving their networks to 5G and each operator environment is different. There is no single open source effort that meets the needs of all operators and network evolution cannot be prescribed to apply to all deployments. Initial 5G deployments are expected to encounter the interoperability challenges that 3G and 4G faced. However, 5G system architecture gives mobile operators more openness than previous generations. Operators and original equipment manufacturers may leverage open source principles in order to stay or become competitive in the marketplace.

Based on the white paper, “The Status of Open Source for 5G”, by 5G Americas