The race to 5G is intensifying as exemplified by a number of public announcements made by leading mobile operators. However, deeper conversations with service providers yield a very simple but important question. How will we make the investments in 5G upgrades profitable?  The bet is that 5G technology will support massively scalable, low-latency-enabled applications that in turn will open up new ecosystems, business models, and creativity across the enterprise and residential markets in every industry.

While industry conversations revolve around these new services, we should not dismiss the fundamental role that the IP network plays in delivering them. The step to make your IP transport network ready for 5G requires some thorough analysis. Don’t think of it as simply one more network upgrade—5G brings new demands on your transport network that necessitates new capabilities.

Building a 5G IP transport network with the right attributes will be a strategic asset for service providers as services evolve over the next decade. Let me expand on a few of these critical attributes that leading 5G transport networks need to provide.



The days are gone when service providers rolled out multiple transport networks to support different services. A modern transport network is converged and capable of concurrently supporting:

  • Fixed and mobile consumer broadband
  • Enterprise, small and medium businesses
  • Retail and wholesale business models
  • Real-time immersive experiences
  • IoT connectivity and value-add

To deal with the complexity of transporting multiple services over a converged network, it is essential to simplify the underlay network across network domains. In just a few years, Segment Routing has emerged as the foundational technology to make networks simpler, as it removes protocols (e.g., LDP, RSVP-TE) and becomes more scalable. By 2019, 60% of the top service providers in the world will deploy segment routing in their networks. This frees up the network from maintaining per-flow states while Segment Routing powers a unified xHaul network fabric.

As some legacy RAN protocols (e.g., CPRI) may never go away, the packet-based transport network must also be able to encapsulate and transport them in order to support any fronthaul RAN, midhaul RAN, and backhaul architectures.



With convergence comes the need for flexibility. The transport network must support a wide range of requirements as not every application is the same – some are latency-sensitive, while others are bandwidth-hungry and do not have the same requirements vis-à-vis the network.

Network slicing turns out to be the technology of choice to custom fit 5G networks to specific applications (e.g., allocate a piece of an operator’s mobile network for different use cases, subscriber services, and classes of customers).

At the transport level, Segment Routing traffic engineering capabilities help to instantiate these network slices by making multiple optimizations of the same physical network infrastructure along various dimensions possible—one can be optimized for low-latency, a second one for bandwidth, and a third can offer disjoint paths on two distinct planes.

At the service level, Ethernet VPN, capable of delivering Layer 2 as well as Layer 3 VPN services, helps to enable network slices and offers a unique control plane extending from Access through Edge to WAN, bringing further simplification.

Another important driver for flexibility is the ability to implement network delivered services in distributed locations that are closer to the end user.  The goal here is to improve service experience while reducing the load on the transport infrastructure and minimizing the blast radius of any possible failures. Network-oriented edge sites—where virtualized network service functions, content infrastructure, and user applications are deployed using commercial off-the-shelf equipment—are expected to proliferate. This creates a strong dependency between the transport infrastructure and these distributed edge sites, and it is important that the control and data planes get closely coordinated to allow end-to-end services to be built in a seamless fashion.



Timing and synchronization are of the essence in 5G mobile architectures. If not properly handled, mobile network efficiency and reliability can be impacted greatly, leading to unhappy customers that suffer from a really poor user experience.

A successful strategy combines located time sources, such as GPS, and a well-designed network to carry frequency and time through a combination of Synchronous Ethernet and Precision Time Protocol (PTPv2 or IEEE 1588).

With increasing radio density and expanding in-building coverage, it is becoming more and more difficult, and expensive, to deploy GPS receivers, especially in more challenging locations. Therefore, the ability to deliver time over the transport network will be an essential component of 5G xHaul.



With increase in network size, the span across multiple network domains, and the high volume of xHaul network configuration changes put automation front and center to a successful 5G implementation.

At the device level, the ability to program using YANG data models—model-driven configuration—with highly performant communication protocols (NETCONF, gRPC, …) has been widely embraced by the industry and is starting to spill over into organizations such as xRAN. A similar model-driven paradigm is being used to extract operational data at very high-frequency—model-driven telemetry—to get real-time visibility of the xHaul infrastructure.

At the network level, it is important to have the capability to orchestrate, manage, and automate the network and its services. Cisco provides comprehensive lifecycle automation to let you operate multiple components/resources—IP transport, network edge sites with virtualized functions, and mobile core—all components of a 5G network slice.

Cisco Network Services Orchestrator provides orchestration and lifecycle management of hybrid networks, while Cisco Crosswork and its associated applications enable automation of the operations life-cycle.



With an unprecedented surge in the number of devices getting connected to the network, the attack surface is getting bigger. The network must be secure, and security begins from being able to trust each system which requires continuous innovation and verification.

With largely expanded 5G networks, most aggregation devices will be placed in untrusted or partially trusted environments, it becomes imperative to quickly detect potential breaches and compromises within the network infrastructure.

The foundation of a trusted network is trusted devices, and all trust must begin in hardware. With hardware-rooted secure boot infrastructure, Cisco platforms provide strong protection against firmware and operating system compromises. This, coupled with advanced runtime OS, control-plane, data-plane, and user-plane protection, allows Cisco platforms unique capabilities to establish and maintain trust in exposed environments.



RAN disaggregation enables improved resource efficiency—matching an allocated resource to actual (time-varying/diurnal) demand, hierarchical mobility, improved scalability, new use cases, flexible workload placement, new consumption models, and multi-tenancy— facilitating deployment of shared systems.

Open, multi-vendor interoperable, bandwidth efficient front-haul interfaces address key operator requirements: à la carte RAN procurement, flexible architecture, agile service delivery, and lower TCO. By and large, making RAN and front-haul network transport investment decision separate prevents proprietary RAN lock in.


All these capabilities are critical to make your transport network ready to support and deliver the upcoming wave of 5G services.

Cisco is ready today and committed to providing an xHaul network that is agnostic to the radio provider, while enabling CapEx/OpEx savings as well as new revenue streams via the tenets of convergence, service flexibility, trust, automation, and open standards-based networking. More than 25 tier-1 service providers around the globe have deployed Cisco IP networking capabilities in their mobile xHaul network with many new wins in the last 12 months.

If you want to learn more about Cisco 5G xHaul transport solution, here is a list of great resources:


Sumeet Arora

SVP Engineering

Core Software Group - US