How CityFibre Delivered a Full Fiber Solution From Calix To Unlock the U.K.’s Digital Potential

Calix partners with innovative internet service providers (ISPs) around the world to deliver the benefits of next-generation fiber broadband. In markets where fiber penetration has been historically low—and consumers and businesses are underserved by aging copper-based networks—fiber networks are having a transformational impact on communities of all sizes.
 

One such market is the U.K., where CityFibre—a Calix customer since 2018—is building an end-to-end fiber network that's revolutionizing the country’s digital infrastructure. CityFibre operates the U.K.’s second largest fiber network and expects to build out its “full fibre” network to a third of the U.K. by 2025. This includes connecting 8 million homes across more than 285 towns and cities, alongside 800,000 businesses, 400,000 public sector locations, and 250,000 5G mobile access sites.
 

CityFibre’s wholesale customers span several verticals, including residential broadband, smart city applications, public sector, and advanced business services. It provides tailored solutions for each segment, allowing its wholesale customers to get up and running quickly on one of the country’s most advanced networks.
 

Taking on the Competition With an Open Access Model

For CityFibre, a wholesale open access model was the lynchpin in their strategy. In the U.K., the market was quite underserved by the incumbents—who were static in their approaches. Copper was the only option, and this made the market ripe for new growth. The true opportunity was with fiber, which CityFibre embraced back in 2018. Today, CityFibre’s network already serves over 2 million homes, with services to all those premises delivered exclusively over Calix GPON technology. More recently, they announced the deployment of XGS-PON across their footprint.
 

With the move to XGS-PON, CityFibre will offer speeds of up to 10G—around ten times the capability of its current G-PON network—meeting increasing customer demand for high-bandwidth services. As well as faster speeds, XGS-PON allows CityFibre to support more customers on each OLT port. This enables substantial improvements to network efficiency, reducing waste and power for a better lifetime TCO.
 

But it’s not just the technology that’s at play here. As CityFibre’s CTO David Tomalin states, “Success can’t be an activity undertaken by a single provider in the U.K. If we want to change the infrastructure holistically, we need everyone working together. The best way to do that is to enable the whole community to use fiber and bring different products and services to market segments. By harnessing this capability through a wholesale open access model, we can drive infrastructure innovation across the U.K.”
 

And this is only done with partnerships across the community and in technology that can scale and transform a business into a fiber powerhouse.

How To Scale a Network Into a Fiber Powerhouse

With over 30 ISP partners serving residential and retail markets, plus over 1,500 partners in the business channel (including government and education segments), CityFibre’s network needed to be agile enough to flex with the needs of their partner ecosystem. A fiber network can do this, but it takes strong technology partners to understand how to position it beyond just the physical infrastructure.
 

To bring this vision to life, CityFibre worked with Calix to build one of the world’s first software-defined access networks. This secure network is built on Calix Intelligent Access EDGE™—using the E9-2 Intelligent EDGE system and the E7-2 —and powered by the Calix Network Innovation Platform (AXOS^®). Leveraging this architecture, CityFibre provides its wholesale customers with unprecedented levels of network programmability, intelligence, and automation—enabling them to offer advanced products and services to their end users.
 

The Intelligent Access EDGE solution was key to enabling this technology migration. By decoupling the hardware and software layers, the solution makes it possible for ISPs to trust the performance, capability, and scalability of CityFibre’s access solutions. It also allows the adoption of new physical layer technologies in the access network quickly and cost-effectively. All of this is enabled by the industry leading work on the service abstraction and common data models by Calix to provide a common operating environment for all networking applications, regardless of the underlying technology.

Unlocking the Future by Creating an “Incubation Engine” With Calix

The right technology partner is someone who understands the culture that depends on that network. For a market challenger like CityFibre, that partnership is critical to enable their success and to compete with the incumbents. It must do more than just work for the partners using the wholesale open access model and for the residents that subscribe to it. It must elevate and simplify end-to-end—all the way to the premises. For its long-term vision CityFibre requires a long-term partner that’s reliable, trusted, and used to taking on the big players in fresh ways.
 

“As true market challengers, we don’t just look at the next three years. We look at a five- or ten-year perspective and ask, who we can trust to help us build the U.K.’s most intelligent full fiber network? We then evolve that network over time as we accelerate to serve a third of the U.K. market and beyond. To do this, we need forward-thinking partners like Calix that are innovative, agile, and able to adapt technically to help us achieve our mission,” Tomalin states. “Getting it right delivers a win-win for CityFibre, Calix, its ISP partners and the U.K. economy at large.”

Watch the interview with CityFibre’s CTO, David Tomalin, to learn more about how they partnered with Calix to roll out FTTP in the U.K.