Is Your Backhaul Network Ready for 5G?


Blog - Is Your Backhaul Network Ready for 5G?

In this blog, we consider the impact of 5G on network backhaul and how Service Assurance needs to evolve to ensure backhaul doesn’t become the weak link in delivering on 5G performance expectations.

In this, the fifth and final blog of our series on automated Service Assurance, we consider the impact of 5G on network backhaul and how Service Assurance needs to evolve to ensure backhaul doesn’t become the weak link in delivering on 5G performance expectations.

New applications bring latency center stage

While previous generations of network backhaul have continuously expanded link speed and capacity, the introduction of 5G has moved latency to the forefront of critical performance factors. This has been driven by emerging 5G standards that have introduced a trio of new core capabilities—enhanced mobile broadband (eMBB), ultra-reliable low latency communications (URLLC), and massive machine-type communications (mMTC).

These three prototypical use cases are helping to realize a suite of consumer applications such as virtual/augmented reality, multi-player gaming and autonomous vehicles that weren’t previously possible. Supporting these new applications is dependent on the ability of 5G devices to instantly and continuously communicate with one another, which is an essential aim of URLLC. As a result, there’s been an order of magnitude shift in the end-point response times needed, going from 10 milliseconds for LTE to less than 1 millisecond for 5G.

5G backhaul is part of a more complex network with much more stringent performance requirements

Backhaul Complexity

5G backhaul is part of a more complex network with much more stringent performance requirements

On top of this dramatic change in latency requirements, impact on network backhaul is further increased by the additional architectural complexity of 5G in terms of Cloud RAN, distributed antenna systems (DAS) and small cells. The bottom line? Along with delivering robust speed and capacity, network providers should carefully plan and strategize a latency budget that specifies how backhaul end-to-end latency needs will be allocated and met in the era of 5G.

Transitioning from a dedicated network to a fluid network

The advent of 5G is rapidly moving away from the one-size-fits-all dedicated network of today’s backhaul toward a more fluid system that can accommodate and guarantee the performance of virtualized network functions and network slices. (For more about network slicing, refer to our earlier blog on this topic.)

Within the overall network system, each network slice has its own uniquely different performance targets, but all of the slices utilize the same physical backhaul infrastructure. This configuration brings a completely new layer of complexity to testing and assuring the performance of backhaul. The support of end-to-end speed and latency performance targets must now be accomplished across a mix of network slices and virtualized infrastructure components.

5G slicing and virtualization create a more fluid network

The Fluid Network

5G slicing and virtualization create a more fluid network

Go cloud-native for a fluid network with fluid assurance

As backhaul assurance experts, the team at Spirent understands there is an evolution to 5G, and that previous assurance models need to be updated and augmented with a new approach that’s as fluid as the network it supports. This model must be able to cover all key dimensions of performance, including latency, speed/bandwidth, and network slicing.

Even for those just beginning the journey to 5G, who may still have a hybrid physical/virtual network in place, there are proactive steps that can be immediately taken today in preparation for the future.

At Spirent, we recommend the migration of backhaul service assurance to a full cloud-native architecture as soon as possible. This move gives operators the flexibility to validate backhaul performance regardless of the network architecture. It supports the use of virtual test agents (VTAs), which allow synthetic traffic to be inserted and performance to be assessed in the virtual network. At the same time, physical test heads are able to perform the same function in the physical network, with virtual and physical elements all directed and coordinated under a common cloud-native controller.

A cloud-native assurance architecture is a critical enabler of automation of backhaul workflows. The open nature of the architecture allows assurance functions to be integrated with network management and back office systems quickly and cost-effectively – making complex workflow automation feasible. (For more about 5G Automated Assurance, go to the first blog in this series.)

Cloud-native Active Assurance Architecture

Cloud Native Assurance

Cloud-native Active Assurance Architecture

5G backhaul best practices and birth certificate

Once a fluid assurance system is in place, Spirent recommends using synthetic traffic to actively test speed and latency. Active testing should be performed across the entire backhaul network segment as well as end-to-end network slices. This is done to accurately determine the interaction of backhaul performance with slice performance.

Ideally, this active testing should take place during the initial backhaul service activation—before carrying live customer traffic—creating a kind of “birth certificate” benchmark that indicates the system’s state at the moment it is turned on. After that, activation tests and monitoring should be continuously conducted on a 24x7 basis so that performance degradations and faults are proactively detected, isolated, and corrected before becoming critical issues in violation of service-level agreements (SLAs). (For more about fault isolation, see this previous blog.)

As an additional step toward 5G, many providers are upgrading their 10G backhaul to 100G links. To actively assure these high-speed links, physical test heads are required that support full 100G line rates in measuring performance. For portions of the network with 1G and 10G links, virtual test agents may be used to evaluate performance across the backhaul and relevant end-to-end network slices. Currently, Spirent is the only assurance company able to actively test 100G links at full line rate.

To host VTAs and also provide flexible support for hybrid networks, virtual test platforms (VTPs), which are essentially low-cost generic computers, are utilized. When common NFV infrastructure (NFVi) is not available, VTPs offer a cost-effective solution for deploying VTAs anywhere in the network.

Unified Active Assurance of 5G Backhaul and Network Slices for an End-to-End View of Performance

Backhaul Assurance

Unified Active Assurance of 5G Backhaul and Network Slices for an End-to-End View of Performance

 Assuring the promise of a fluid 5G-compatible backhaul

As 5G evolves, a fluid, cloud-native backhaul assurance approach positions providers for future dynamic backhaul-related enhancements such as integrating a meta-layer of software-defined networking (SDN) controllers. Such changes will allow the backhaul network to become as fluid as the rest of the increasingly virtualized network.

Without a doubt, 5G is bringing exciting and challenging changes as well as stringent new performance requirements to transitioning telecommunications networks. Rather than waiting to be overwhelmed, providers need to take action now. Starting the process means making their backhaul systems more fluid and effective in terms of evaluating end-to-end latency budgets, adopting a cloud-native assurance architecture, upgrading to full line-rate 100G testing, using virtual test agents for continuous synthetic traffic testing, and more.

Each and every step along the way, the experts at Spirent are ready to help. We’re here to make certain that your backhaul (and every other part of your network) is thoroughly and continuously tested and up to the task of delivering on the extraordinary promise of 5G.


Promise. Assured.




Ross Cassan
Ross Cassan

Sr Dir Mobility Strategy, Lifecycle Service Assurance

Ross Cassan是思博伦网络、应用与基础设施部门移动基础设施事业部的产品营销总监,负责思博伦旗舰产品Landslide的战略策划、营销与推广。思博伦Landslide支持对整个移动与Wi-Fi生态系统进行端到端测试。此外,他还是宽带论坛(Broadband Forum)与TIA等多种技术标准机构的主要贡献者。Ross于1999年加入思博伦,曾分别在硬件和软件平台的产品管理及营销方面担任过职务。在加入思博伦之前,Ross在Newbridge Networks和Nortel担任营销职位。