Where do we spend most of our lives? Indoors, behind layers of concrete and steel, and underground, exactly where mobile networks struggle most.

Originally published in Forbes Magazine as part of CTO Stephen Farrugia’s contribution to the Forbes Technology Council, this article makes the case for designing connectivity into major infrastructure from the very first sketch.

In 1962, The Jetsons enjoyed seamless video calls and never dropped a signal in a lift or a flying car. A generation later, Back to the Future II imagined a 2015 of hoverboards, flat screens and voice-activated everything.

Today, we mostly inhabit that imagined future. The smartphone has transformed how we work, play and connect, and made constant wireless access an everyday expectation.

Yet in science fiction, connectivity simply existed. No one paused to ask who builds the infrastructure, who pays for it, or how a signal gets through the concrete and steel of the indoor and underground environments where we spend most of our lives.

As much as 80% of mobile traffic originates indoors, in apartment towers, shopping centers, hospitals and transit tunnels. However, the macro networks our industry has engineered outdoors were never designed to penetrate deep underground or dense interiors. We have systematically underinvested in the spaces where we spend much of our time.

Why the gap persists

Across a career spanning broadcast, public safety, rail and industrial networks, I have found the causes are mostly structural.

Macro networks have clean economics: one tower, one owner, tens of thousands of users. Every building is a bespoke design with its own owner and its own negotiation, leaving no repeatable unit of deployment to drive costs down. The carrier earns the revenue, the asset owner controls the space, and neither can justify the investment alone.

Coverage obligations are also measured outdoors. What gets measured gets funded.

Designing connectivity in from day one

As countries build generation-defining infrastructure – road and rail tunnels, smart stadiums and hospital precincts – connectivity is too often bolted on late in construction. The penalty is invisible on a drawing, but painfully visible in the field.

Space, power and pathway are almost impossible to add later, so a project without reserved communications rooms and cable routes caps its capacity on opening day. Antennas go wherever room is left. Certified fire-rated structures get cut open. In a live tunnel, work is confined to short overnight possession windows.

I have seen retrofits where the cable was a rounding error and access was the entire budget.

Three networks, one space

Tunnels and precincts also need several networks at once: public cellular for customers, operational networks for systems such as driverless train signaling, and resilient public safety networks. Each has a different owner, assurance regime and life cycle.

Public safety demands redundancy that commercial coverage does not. Operational networks usually prohibit shared logical paths. Cellular refreshes every five to seven years, while signaling may run one standard for 20.

Combine them carelessly and you either gold-plate the commercial layer or under-build the safety-critical one. Settling at concept stage which layers can share, and which cannot, avoids both.

Choosing the right model

Procuring each layer separately leaves duplicate infrastructure competing for space that rarely exists, and no one accountable for the whole.

Many owners now appoint a single independent operator, or neutral host, to design, build and run one shared layer. It suits constrained, long-lived, multi-tenant assets such as transit systems, airports and hospital precincts. A mine or port running its own operational network is often better keeping control, and a modest single-carrier building may need only an off-the-shelf solution.

The trade-off is control. Owners gain accountability and lower lifetime cost, but cede part of their asset for decades, so the contract deserves more scrutiny than the technology.

Long concessions change engineering behavior, too. A partner accountable for performance in 2045 builds in headroom today: spare fiber, extra conduit and room for future carriers and bands. In return, the owner must guarantee access and agree in advance how technology refresh is triggered and funded.

Three principles for smarter connectivity

Whatever the model, three principles apply.

• Design it in: At concept design, reserve rooms, power and pathways with stated spare capacity, and name one accountable owner for the communications layer before the first tender.

• One program, multiple needs: Where space is tight, share passive infrastructure such as pathways, cable and rooms, but keep active layers separate where availability, security or refresh cycles diverge. Confirm early that safety authorities will accept it.

• Accountability follows the asset: Contract for outcomes: availability, coverage measured where people use the network, time to restore, refresh obligations and a handback standard. Then monitor continuously, because a 30-year asset is judged on an ordinary Tuesday in year 12, long after handover day.

Final thoughts​

The spaces we build now will shape our societies for decades. Designing connectivity into them, and holding someone accountable for it across their whole life, will decide whether they are as connected as the future we always imagined.

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