Imagine a society where public services are intrinsically linked. Citizens could be notified on their smartphone of a late running train service, with alternative routes shared. Driving into the city centre, a message could flash up on their car dashboard, letting them know which public car parks have free spaces. Walking to their office, their fitness tracker could monitor their steps and calories burned, and alerting their employer and health insurance provider of their wellbeing. Mood recognition sensors embedded into the individual’s office equipment could automatically adjust the lighting and temperature to help them achieve a sense of calm after a stressful commute.
These services are being made possible as our connected society moves towards fixed-mobile convergence, the emergence of the Internet of Things (IoT) and M2M services and the transition towards 5G network speeds. But in this ever-smarter world, global data traffic and smartphone usage has exploded. This has placed significant pressure on the capabilities of Communication Service Providers’ (CSPs) mobile backhaul networks to manage this massive surge in capacity demand.
As a result, managing mobile backhaul transformation and enhancing network capacity economically is one of the most critical challenges that service providers will face over the next five years. In this article, I will explore some of the strategies that CSPs can adopt to overcome these challenges and deliver business and operational efficiencies.
Which backhaul infrastructure will help enhance my network capacity?
CSPs must first identify the most appropriate backhaul infrastructure investments for their business model, based on the geographic and economic variables within the local area. In mobile-only operator environments, emerging economies or where remote access considerations and wireline infrastructure costs pose significant challenges, wireless microwave backhaul, or a combination of backhaul technologies, will continue to be deployed.
The case for fibre
In mature markets – especially in the context of operator Fixed-Mobile Convergence (FMC) – fibre backhaul represents the most attractive option for supporting the bandwidth demands driven by increased cell densification, Heterogeneous networks (HetNet – the use of multiple access nodes in a wireless network) penetration and the future requirements of 5G gigabit services.
Fibre is a key enabler for transformation, as where existing fibre infrastructure exists, it can be leveraged by fixed-line CSPs to support backhaul deployments – for instance, when a fixed service provider merges with or acquires a mobile operator to provide bundled services over a converged network. In this context, the fixed service provider will typically have an established fibre-based core, distribution and access (FTTx) network infrastructures that can be organically extended to support fibre backhaul connectivity to the mobile cell-site.
CSPs will continue to employ a mix of backhaul technology options, such as microwave, copper, and fibre, to manage different cost and access business models. This will most often be the case when an operator already uses a specific backhaul technology and needs alternative options to support the introduction of new services, and increased cell densification, while reducing deployment costs. In this context, a variety of backhaul architecture options can be deployed together, depending on specific network planning, capacity and access considerations.
The software-defined approach
Deploying SDN and NFV in tandem represents an attractive option to organisations who are keen to avoid intensive infrastructure investments across their network. The platform they provide is already playing a critical role in supporting seamless backhaul connectivity through automation and dynamic routing, helping to reduce deployment costs. They can be applied in a variety of use cases, but they possess three core tenets which are critical to a successful mobile backhaul transformation:
• Virtualisation
NFV enables a set of network functions in the physical, or legacy, network to be virtualised by deploying them in software packages – on servers in a data centre for example – that can be linked to create the service supported in the legacy network. This is called ‘service chaining’, and it helps reduce hardware deployment costs, while improving the automation and management of the service. In the context of mobile networks, Cloud Radio Access Network (C-RAN) is the main beneficiary: it uses it to virtualise the core network and centralise base-band processing for the RAN. This allows for the deployment of distributed virtual gateways across the network, which help to dynamically manage the traffic generated from the RAN across the backhaul and into the core.
• A centralised control plane
The deployment of an SDN controller is also critical, as it abstracts the network control logic stored in legacy network elements into a unified software control plane. This enables new classes of network services, traffic routing decisions and upgrades to be dynamically orchestrated from a centralised controller and ultimately supports enhanced routing optimisation across the mobile backhaul. And of course, this helps to improve both on-demand service delivery and customer experience, due to an increase in quality of service.
• Improved mobile backhaul performance
Mobile backhaul networks can only function effectively when high performance network infrastructures are in place, and supported by a flexible management layer. The employment of selective network virtualisation together with dynamic control plane orchestration, can enhance backhaul optimisation, reduce network complexity and provide seamless connectivity to support operator strategies for migration towards 5G.
Applying this to a business context
If CSPs are to both meet and manage the ever-increasing capacity and service demands of connected society, they must define holistic backhaul strategies that are aligned to their core business models. Here are my key recommendations for CSPs to consider:
• Develop a comprehensive migration roadmap
CSPs must clearly define the incremental strategies they plan to implement to deliver migration in the backhaul that supports the evolution of 3G/4G/LTE towards 5G. These strategies should be tailored to the specific operator’s business model across services, processes, networks and IT.
• Continue to invest in infrastructure
Fibre is a critical enabler in meeting the capacity, speed and bandwidth demands of next generation services and data. CSPs should not therefore, refrain from investing in infrastructure if the specific case demands it. All things considered, many will continue to employ mixed backhaul technology options (such as fibre, microwave and copper) to suit to their specific business models.
• Explore a variety of architecture options
The deployment of crosshaul (x-haul) architectures is critical to successful mobile backhaul transformation, as they help to support cell densification, coverage and enhanced traffic capacity management by providing a unified IP network, which delivers seamless connectivity and quality of service from the core to the edge.
• Embrace the software-defined through SDN & NFV
SDN and NFV represent a viable and robust alternative, should CSPs wish to avoid taking the fibre route. By operating C-RAN with baseband and edge node virtualisation, along with service chaining and dynamic routing techniques, CSPs can increase automation in the backhaul and reduce deployment costs.
• Professionalise operations management
Highly advanced operational support systems (OSS) now exist, which help CSPs to monitor, control, analyse and manage backhaul networks. The rationalisation they provide is critical to delivering effective backhaul performance and guaranteeing capacity and service level management, which in turn improves the quality of service and customer experience.
• Consult strategic partners
To ensure the success of any backhaul transformation strategy, CSPs should be open to partnering with the technology vendors or third-party suppliers. These organisations are experts that can act as deployment or outsourcing partners, and provide consultation on both existing backhaul networks and potential strategies for achieving backhaul transformation.
The connected society is making ever-increasing demands for capacity and services in both personal and professional circles; and as a result, enhancing network capacity in a cost-effective manner is one of the biggest challenges facing CSPs today. By adopting some of these strategies however, CSPs can make this process much easier and provide services that meet and exceed customer expectations.
