What is Dark Fiber?

When we call Metronet Zing an ‘open-access fiber optic network’ — what do we mean?

The term ‘dark fiber’ is thrown around a lot today in conversations about internet connectivity, speed, and democratization — but how many of us actually know what dark fiber is?

Dark fiber refers to unused (commonly called ‘unlit’) fiber optic cable networks. In simple terms — fiber that is not currently transferring data. To really understand what dark fiber is, however, we have to explore one way that this unused cable got into the ground:

Bursting Bubbles 📊

The dot-com bubble was a time period from 1997–2001 which saw rapid internet adaptation. Major telecom providers, wanting to tap into the potential of global internet use, began building expansive (and expensive) fiber optic networks in major markets around the country. These providers assumed that both demand for internet access and data sizes would continue to rise at the same astronomical pace.

However, the market shifted and the bubble popped.

Investment in technology companies was no longer based on market demand, but on high expectations of the future. The telecom providers who had built these vast cable networks had taken on massive amounts of debt to do so and were unable to profit off their use. Paul Starr explains this phenomena in The Great Telecom Implosion:

.. After congress passed the telecommunications Act of 1996, capital flooded into telecom, as existing firms and new ones began building networks over land, undersea and in the air. “Business plans all looked alike,” one industry insider recalls. “Massively parallel systems were being built up.”

Because of this market crash, vast cable networks were left unused beneath our major cities.

Why does dark fiber matter now? 🌐

Technical advances in data packaging have occurred rapidly over the past two decades, exponentially increasing the capacity of these vast fiber networks.

It helps to understand this technical advancement if we think of fiber as a highway. In traditional data transfer, one system uses one lane and simply moves faster to increase capacity. Today’s processes are exponentially more efficient. Columbia’s B. Bathula explains why this unused fiber is so valuable today:

In optical networking, utilizing DWDM (dense wavelength division multiplexing) is analogous to accessing the unused lanes on the highway .. to gain access to an incredible amount of untapped capacity in the fiber.

In other words, Dark Fiber is scalable and fast.

More data. More speed. More possibilities. ⚡️

In its simplest form, dark fiber is untapped potential. Modern technology has made it even faster. In major cities, these dark fiber cable networks are available because of early tech growth.

Here in South Bend, our dark fiber story is different. While fiber networks in major markets were overbuilt, smaller cities like South Bend were neglected. Our next blog will narrow in focus to explore how and why Metronet Zing sought to empower local businesses with fast and reliable fiber connectivity.

Thanks for reading! We are an open-access fiber optic network serving South Bend, IN and surrounding communities. Learn more: metronetzing.org