As traditional telcos map out their long-term broadband strategies, navigating the transition from legacy copper networks to fiber-based passive optical networks (PONs) is a top priority. Network operators know why this migration is necessary: Fiber delivers benefits when it comes to lower maintenance costs and improved customer experience. It’s just good business for telcos to offer their enterprise and residential subscribers reliable, high-speed services with the assurance that their networks have enough bandwidth in place to stay ahead of demand in the future.

In this regard, an investment in a fiber PON is an investment in a community’s long-term economic health. It’s an invitation for local companies to expand their operations or for new companies to relocate to a community that is future-ready with fiber infrastructure.

Tipping Points

The “Why PON?” question is easily answered. But how does an operator know when to make the leap from a copper network to a fiber PON? A number of tipping points motivate network operators to switch.

Weathering Storms

The threat from extreme weather incidents unfortunately is on the rise. Headlines about historic flooding, out-of-control wildfires and frequent monster hurricanes and tornadoes demonstrate a new reality. Recent catastrophic flooding in Nebraska, Missouri, South Dakota, Iowa and Kansas, driven in part by melting snow, illustrates this alarming trend. Subscribers who recover from these events endure very long restoration times when being able to communicate and access broadband-based services to rebuild their lives is crucial.

Legacy copper networks are particularly vulnerable. They’re less capable of weathering storms than fiber-based networks. PONs are not immune to climate, but climate’s impact on PONs is far less severe, and restoration time can be significantly shorter. For example, repairing and replacing drops at homes and businesses after storms contributes greatly to long restoration times. But the use of fiber optic preconnectorized solutions for subscriber connectivity can reduce this time dramatically, restoring service quickly at the very time they need it most.

Many copper-broadband network operators recovering from catastrophic events choose to rebuild their networks with fiber. That’s an obvious tipping point for the transition. But with the knowledge that extreme storms are on the rise, perhaps the time to rebuild is before a storm even hits. A proactive approach sets operators up for shorter restoration times, benefiting network operators and subscribers alike.

Competing for Subscribers

People’s insatiable appetite for bandwidth, whether at work or home, is driving broadband providers to find ways to stay on top of that demand – and ahead of competitors. Cable operators are extending the lives of hybrid fiber-coaxial networks by expanding the capabilities of gigabit-capable DOCSIS technology to 10 gigabits. With emerging technologies such as 5G and CBRS beginning to take hold, fixed wireless operators will offer better broadband alternatives to those delivered by DSL over legacy copper networks.

This fixed wireless momentum is evident in many ways. For example, cable operator Midco is expanding its broadband reach with fixed wireless and soon will be in a position to offer wireless 100 Mbps service.

Legacy copper infrastructure is challenged to keep up in this evolving competitive environment. The less-capable broadband experience DSL offers will incentivize subscribers to shop for better broadband elsewhere. Many telcos see this threat as a tipping point to get ahead of the competition by transitioning to fiber PON now.

Driving Down Opex

Operating costs for copper-based networks often are overlooked or thought of as simply a given when it comes to doing business. But these costs could tip the scale significantly in favor of transitioning a network to fiber all the way. Maintaining a copper network is inherently more expensive – much more expensive – than the maintenance costs that come with a PON.

Truck rolls alone are a big factor. With truck roll costs averaging anywhere from $160 to $600 per instance by conservative estimates, network operators should be in the business of reducing them across the board. Some estimates peg truck roll costs at $1,000 or more when all expenses, including fully loaded labor costs, are captured.

By their very nature, PONs require fewer truck rolls. Fiber is not nearly as susceptible to water, salt and other external factors that impact copper networks, often leading to service degradation and associated trouble reports. Ask any telco with an extensive copper network about the aftermath of a sustained rain event. Heavy rain often leads to a spike in trouble tickets and truck rolls – or even multiple truck rolls per report.

What’s worse for network operators is operating both a copper network and a PON simultaneously. Moving to a fiber-based network will not provide dramatic operational savings if a network operator continues to operate a copper-based network at the same time. A cutover plan should include strategies to migrate copper-based customers to new PON facilities as quickly as possible, even for lifeline dial-tone-only customers. It’s important to recognize that regulatory implications vary by jurisdiction and must be understood and considered for individual cutover plans.

Migrate Strategically

Luckily for telcos, a number of migration strategies can ease the process of overbuilding with fiber. A strategic migration plan can help operators minimize both costs and service disruptions, allowing telcos to seize PON-based service revenues faster.

Repurposing Cabinets

Copper-based networks feature cabinet frames in the field for cable distribution. When migrating to PON facilities, many cabinets can be retrofitted to house fiber distribution panels to manage fiber splits in the network. By repurposing existing cabinets rather than installing new fiber cabinets, some network operators have achieved a 40 percent savings. It doesn’t take long for that 40 percent savings per cabinet to add up to tremendous cuts in network construction costs.

The benefits go well beyond just saving money. They include:

  • Aesthetics – Leveraging legacy cabinets saves network operators from needing to install new ones, which is much more appealing in many neighborhoods.
  • Permitting Approval – Using existing cabinets often means there is no need for the permitting process, a benefit that could be considered priceless.
  • Speed of Deployment – Repurposing existing cabinets for PON use often can be accomplished in a day or less, compared with weeks or even months for building and placing new ones.

Additionally, these cabinet repurposing or reskinning projects don’t interfere with the existing copper facilities, allowing network operators to continue to serve customers while the transition to an all-fiber network is underway.

Leveraging Aerial Assets

Many telcos have extensive aerial copper plant that should be leveraged to the fullest extent possible during the transition to PON. Strategies can include lashing fiber cable to existing copper cable. This approach can be much more efficient than installing new lashing lines to support fiber cable, especially on space-constrained poles. By lashing to existing cable where network operators already have rights, operators also potentially save significant time associated with rights of way and other “red tape” delays.

A variety of solutions are available from vendors, including Corning, that help facilitate this process. Corning’s FlexNAP system, for example, can be lashed to existing aerial copper facilities, providing preinstalled connectorized fiber network access points along network operator–specified locations. Network operators have used this approach for PON overbuilds to great effect in multiple projects across North America.

Act Now

Transitioning to a fiber PON-based model grows in importance every day. Community economic goals dictate a robust, ubiquitous broadband network that can sustain economic development, retaining and attracting the businesses that are main contributors to a healthy tax base. As telcos evaluate the timing of their transition to PON infrastructure, certain tipping points may make it clear that the time to put their eventual migration plans into action
is now.

Next in this series, we’ll explore network convergence – how the infrastructure you place today could serve to provide many more services (and revenue streams) than single-purpose-built networks.