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Dark Fiber vs Lit Fiber, What is Right for Your Enterprise

The Internet has come a long way since the days of dial-up when in order to access the web, your computer borrowed your phone line to temporarily transmit data instead of voice. Those limited, low-speed connections have long since been replaced with new technologies, the latest and greatest of which is fiber Internet, which offers your business the quickest internet speeds possible (often several gigs) and the high bandwidth, low-latency features that offices of all sizes have come to rely on for smooth business operations. But once you settle on fiber, there’s one more choice your business needs to make: dark fiber vs lit fiber? What’s the difference between the two and which fiber option is the best choice?

What is the difference between dark fiber vs lit fiber?

The differences between dark fiber vs lit fiber can almost be deduced from their names alone. Like a stage that’s gone dark on Broadway, dark fiber simply refers to a fiber connection that is not currently in use. Lit fiber on the other hand is more like a concert—it’s “live” and providing a high-bandwidth connection. Dark fiber becomes lit fiber when someone adds electronics to it and starts using it. But just like the vast differences between a Broadway play and a concert, these two types of fiber connections have different performance capabilities, and there are several nuances between the two to note before settling on a solution.

Dark Fiber Pros and Cons

Availability and Scalability

Because dark fiber isn’t in use, it allows an enterprise to control what the fiber is used for, and the connection is completely dedicated to the business that purchases or leases the connection, which provides data security. A key component of the scalability of dark fiber is the ability to develop protocols and quickly change bandwidth depending on the business needs. A dark fiber connection allows enterprises, health care organizations or governments to send data (and unlimited amounts of it) straight from point A to point B, if they so choose, making it fast and efficient, as well as secure. This quick scalability comes with one primary constraint: the dark fiber set-up will take more time for the customer initially since they will need to install and manage the electronics that are going to be used between their locations.

As for availability, it’s important to note that dark fiber may not be available everywhere. Particularly in rural environments or locations where a fiber network is not set up, dark fiber can be hard to come by (Luckily DQE’s dark fiber service footprint spans 4,000 miles; check out our network map).


Businesses are able to lease the dark fiber strands from a network provider that builds their own network and offers this product option, saving the company who wants this type of connection the hassle of running the actual cabling themselves. Not just anyone can install fiber networks either – there are regulatory qualifications and processes that must be followed including having ROW agreements in place before permitting. Installing fiber can cost hundreds of thousands of dollars, so utilizing an existing dark fiber vendor presents an immediate advantage to businesses that need the high speeds and customization that dark fiber offers. Any business choosing a dark fiber network should consider the initial costs in bringing the network online, but in the long term, businesses craving customization and security will get what they pay for with a dedicated, fixed-cost dark fiber solution.


The other factor to consider when choosing dark fiber is ongoing management. While the fiber provider will make sure the fiber backbone network (cables) are functioning and provide ongoing operation and maintenance on the fiber network, the responsibility for the company’s electronics and network operations falls to the company using the connection. Ensure that your business has the staffing, resources, money and know-how to seamlessly operate your dark fiber network.

Lit Fiber Pros and Cons

Availability and Scalability


Like skipping the line at an amusement park or walking into a restaurant with no wait, the biggest pro of lit fiber is that it is ready right now. The convenience is undoubtedly the biggest pro of lit fiber services, which are known by several names, including Wavelength or Metro Ethernet or Internet Services.

When your business is ready to start employing fiber optics, joining a lit fiber network is a seamless, quick experience with little disruption and without the longer set-up time typically associated with dark fiber services. Something to consider prior to choosing lit fiber is scalability. Unlike a dark fiber network where scaling for bandwidth needs is managed completely by your company, obtaining more bandwidth on a lit fiber connection comes with additional costs and planning! (DQE’s lit fiber services can help you avoid any downtime. Learn more about DQE’s Internet Services.)


Increasing the bandwidth also has associated costs. It’s likely that when you choose to add more bandwidth, your fiber provider will increase your monthly fees. So if quick and frequent bandwidth changes are in order, or if your company has large bandwidth needs, a dark fiber solution may be a better fit for your business financially due to the fixed cost nature of dark fiber. On the other hand, if your bandwidth needs are well-defined, not likely to change dramatically over time, or your company generally requires low bandwidth, a lit option is your key to cost savings. In general, understanding your bandwidth needs will help you determine the best product for your business.


Hassle be gone: lit fiber comes with the added bonus of passing the responsibility for the operation of your fiber network off to an expert. Equipment maintenance responsibility falls to the service provider, so you are able to focus on your business’s operations. That’s why lit fiber is often the go-to choice for businesses that don’t have specific security and ownership needs.

DQE’s Fiber Services

If the information above has helped you settle on a dark fiber vs lit fiber solution, DQE is primed to help better than ever before.

In 2021, DQE announced additional focus on its lit fiber services to match industry demand. According to DQE CEO Jim Morozzi, DQE’s dark fiber product targets large, sophisticated companies that are capable of managing their own networks. DQE is also a well-trained hands-on service provider that employs the newest and best techniques to manage lit services for a wide array of companies across an expanding footprint. Read the entire interview with Morozzi in this Smart Business interview.

With a fiber network that spans 4,000 route miles and growing, we can help you bypass any sourcing issues and set you up with the right Dark Fiber, Metro Ethernet, Wavelength or Internet services. Our full suite of fiber-based internet solutions can address businesses’ unique requirements and create custom solutions that are tailored to your needs.

To learn more about how DQE can partner with you to customize solutions, contact us today.

Tags: dark fiber, lit fiber