Explore Cisco
How to Buy

Have an account?

  •   Personalized content
  •   Your products and support

Need an account?

Create an account

Simplifying 5G Delivery to Accelerate Wholesale Services

Colt optimizes its IQ Network for mobile service providers with direct API programmability

The customer summary

  • Customer name: Colt Technology Services
  • Industry: Telecommunications
  • Location: London, UK
  • Number of employees: 5,000


Business challenge:

  • Need to increase investment in deep fiber connections.
  • Want to differentiate services from other mobile network operators.
  • Seek to reduce operating expenses without a major capital investment.

Network solution:

  • Deployed a Cisco-powered segment routing and Ethernet VPN-based architecture, which can be extended using standards-based APIs.
  • Enabled self-provisioning of guaranteed SLA services based on latency and bandwidth demand.

Business results:

  • Lowered costs because of fewer site visits, greater spectrum utilization, and the sharing of pooled resources.
  • Capitalized on Open RAN initiatives to ensure that there are open APIs between them.
  • Accelerated customer service delivery times.

5G will dramatically change the architecture of mobile networks, driving an even greater need for reliable, high-bandwidth fiber backhaul. The Colt IQ Network is perfectly matched to 5G as it offers on-demand flexibility and scalability combined with the reliability and capacity on which mobile networks depend. Colt has worked closely with Cisco to design a network architecture that is simple to operate, highly available, and capable of delivering innovative network services. This enables Colt and therefore Mobile Network Operators to benefit from faster time-to-market.

Peter Coppens, Vice president, Product, Colt


Moving to 5G

Since the 1990s, the role of the mobile phone, and the cellular network, has changed dramatically. 5G is the next step in this evolution. This fifth-generation technology provides new services at exceptional scale, data rates, and low latencies. Alongside the existing services, new services such as autonomous vehicles, virtual and augmented reality, and smart cities are possible with 5G. But the gigabit speeds, sub millisecond latencies and the ability to connect over 2.5 million devices per square mile places unprecedented demands on the network.

Colt sought to create its global Colt IQ Network to serve as a foundation for mobile service providers (MSPs) to provide rapid 5G deployment and effective service delivery to consumers. For MSPs, 5G will require macro and small-cell densification. This density will lead to a demand for increased investment in deep fiber connections to next generation antennas and small cells.

Microwave backhaul is still prevalent from the cell site to a first routed hop. The challenges microwave presents around cost, variable bandwidth, and high-link latency are exacerbated by the demand for 5G service offerings that can be monetized. Many MSPs can’t justify the business case for either dark fiber rental or their own-installed fiber. The bandwidth and service utilization threshold would typically be far higher than an individual MSP would require. Sometimes fiber isn’t accessible at all because of planning permissions or local regulations.

The solution to these issues is to share fiber costs among multiple MSPs. Ideally, creating managed services could offer significant reductions in operational expenditures without a major capital investment. Although sharing transport connectivity lowers costs, the lack of differentiated services has been a barrier to adoption.


Sharing connectivity to enable 5G

Colt has a significant global fiber network with paths typically traversing a maximum of 3km from any given location in large metropolitan areas. This network has been combined with a leading-edge, programmable-routing architecture for advanced 5G service enablement. Although the underlying fiber infrastructure is shared, each MNO can have a different service-level agreement (SLA) for their applications.

With previous routing protocols and their highly manual operations, it was a time-consuming process to share a fiber. It also had little no flexibility to enforce strict SLAs beyond 1 x hop. However, Colt deployed a Cisco-powered segment routing (SR) and Ethernet VPN (EVPN) architecture, which is now a vital element of the Colt IQ Network. The openness and programmability of the architecture can be extended to Colt’s customers directly using standards-based APIs. These advancements have provided a long-awaited breakthrough in automation for next generation 5G backhaul requirements. The architecture enables self-provisioning of guaranteed SLA services or network slices based on latency and bandwidth demands.

In regions where deep last-mile fiber resides, such as in the US and parts of Asia, the initial 5G deployments are using CloudRAN. In this case, parts of the Radio Access Network are disaggregated, often into virtualized components. CloudRAN dictates strict latency requirements, which restrict the distance that a centralized and/or virtualized radio component should reside from the antenna. This distance typically isn’t more than 20km and this type of connection (known as front haul) often has a far greater bandwidth requirement.


Reducing cost of ownership

CloudRAN promises to reduce costs through:

  • Greater spectrum utilization.
  • A sharing of “pooled” radio resources.
  • Simpler, cost-optimized antennas that require fewer site visits and can be powered and connected with a single cable.
  • The ability for providers to select best-of-breed individual components and capitalize on Open RAN initiatives, to ensure that there are open APIs between them.

Colt is present in over 850 datacenters globally, which naturally complements the necessity for deep-fiber-based networks for 5G services, including remote compute edge demands.

The Colt On Demand proposition also provides significant commercial advantages because it uses a pay-as-you-go approach instead of standard approaches that are OpEx-based through leased lines or CapEx-based using dedicated self-owned dark fiber. Now accounting is only for the bandwidth and SLA required by the MSP, which allows the cost of upgrades to align to service growth..


Extending SLAs to 5G applications

Colt is in the process of deploying segment routing all the way into the top-of-rack router in their distributed network functions virtualization (NFV) datacenters. The deployment will make it possible to extend path programmability and SLA adherence to applications using 5G.

In addition to the radio components, the virtualized user-plane of a control user plane separation (CUPS) packet core will be distributed deeper into networks. Applications with tight latency and high-bandwidth requirements will follow. This design reduces the processing power required on the mobile terminal, so lighter devices such as augmented reality glasses will be feasible.

By using its own orchestration and automation infrastructure, the mobile service provider can request 5G application-specific SLAs, such as SLAs for bandwidth or latency. These SLAs can be delivered from the Colt IQ network using the standards-based APIs of the Colt IQ network applications. This process removes any manual intervention with significant cost savings and improved time to market.


How self-provisioning works

The self-provisioning of guaranteed SLA services or network slices goes through the following interactions as shown in Figure 1:

  1. The mobile service provider enters Colt’s On Demand web interface and defines:
    • Radio destination (A) and their first hop owned-colocation (B).
    • Bandwidth requirements.
    • SLA level including path disjointedness and limits on real-time latency.
  2. After ensuring an SLA can be achieved without degradation to other current services (bandwidth on demand + access control), the Colt On Demand platform configures the service into NCS5501 PE routers using SR/EVPN.
  3. This service can be fully automated by the integrated Colt On Demand platform using APIs with the MSP’s service provisioning engine.
  4. Streaming telemetry provides near-real time network health parameters ensuring visibility into SLA adherence and potential path optimizations including reporting to the mobile provider.

Figure 1: Colt self-provisioning of guaranteed SLA services or network slices.


Providing resources while reducing costs

Colt can provide the programmable compute and network resources required to get applications closer to end customers. At the same time, Colt can offer the SLAs as a market differentiator and reduce the costs for CUPS and CloudRAN for MSPs.