What is Dark Fiber and How Does It Work


Dark fiber, also known as unlit fiber, refers to fiber optic cables that have been laid underground and do not have service or traffic running on the fiber strands. It is typically used for telecom and network communications. Ultimately, dark fiber provides the maximum level of control for businesses, allowing you to use your preferred protocol and manage your own equipment.

How Does Dark Fiber Work? 

Buying dark fiber cables isn’t the same as buying telecommunication services. Instead, it feels like you’re buying the equipment and doing the rest yourself. For businesses that require high-speed and high capacity, dark fiber allows you to create and control your own private optical network rather than leasing fixed bandwidth. It offers near limitless capacity and provides the assurance of dedicated connectivity. 

Businesses that find dark fiber beneficial are:

  • Manufacturing and logistical companies
  • E-commerce and retail operations
  • Schools
  • Hotels
  • Government institutions
  • Internet providers
  • Telecommunication companies

How To Set Up a Dark Fiber Network 

Businesses can choose between a lit fiber or dark fiber infrastructure when selecting a fiber optic network. Lit fiber services are delivered by a service provider that owns and maintains the equipment to light the fiber. Compared to lit-fiber services, businesses will lease a dark fiber infrastructure and provide their own equipment to light the fiber. They will be able to deploy and operate the equipment required to “light” the fiber and use it for Internet access and communications.

There are different ways to set up a dark fiber network. You can use point-to-point or point-to-multipoint configurations, which are common ways to install dark fiber networks. Dense Wavelength Division Multiplexing (DWDM) is another huge factor in the development and improvement of Dark Fiber. DWDM occurs when multiple data signals are transmitted at the same time through the same optical fiber. 

What are the Benefits of Dark Fiber?

If your business has specific network requirements, then dark fiber is ideal for those that need control of their network infrastructure and require near zero response times for point to point communication. With a dark fiber network, the operator will act as their own ISP and avoid service delays. The benefits of dark fiber include scalability, network latency, security, reliability, and costs. 


When an organization is looking to expand, they might not have the bandwidth to efficiently run their business. The process of requesting more bandwidth from an ISP could take weeks and would cost more in the long-run.

By investing in dark fiber, the company can increase its bandwidth capacity to upgrade the equipment powering the fiber. Organizations will be able to access near unlimited bandwidth and won’t have to deal with additional fees or service delays from the ISP.

Network Latency

Running a dark fiber network requires you to purchase and install your own transmission equipment. This allows you to have control over the network’s latency. If the connection points are close enough, it’s possible to eliminate the transmission equipment and directly connect the points through a router or network hub.

Low network latency is important for companies who depend on fast communication between different point to point communications portals. This is also essential for large data centers that need to quickly communicate with each other. Additionally, the dark fiber speed is controlled by the owner of the lease, so businesses using the technology don’t have to worry about sharing bandwidth with other customers.

Increased Security

The dark fiber network is privately owned and operated by the lease owner, so outside entities can’t track or record the data and information being transmitted through the fiber. This is especially important for businesses and organizations that need to constantly transmit sensitive materials over a secure network, and is especially important for sensitive industries  such as research, defense, financial services, and more.


Operators of a dark fiber network are equipped to handle the necessary repairs and maintenance. As a result, dark fiber networks offer a reliable, flexible, and high-speed bandwidth service that ISP cannot match. When there is a problem with the network, you would have to send a request to the ISP for them to identify and solve the issue. This means that you could end up waiting for a while since they are dealing with other requests.

However, with a dark fiber network, you will have control of the system and resolve the issue yourself instead of contacting ISP to send out a technician. You will also be able to minimize downtime if any problems occur, which is crucial for companies that want to lower costs.


Even though the cost for dark fiber is high, operators who use dark fiber networks can be reassured that the costs for running the network will be beneficial long-term. In comparison with traditional ISP, businesses will deal with the fees increasing for their current level of service.

This will cost the company more than what could have been paid for with a dark fiber network. If your organization has a lot of data that needs to be moved around, it will save you more money to bring up your own dark fiber network compared to paying a large sum for an Internet provider. 

Data Centers and Dark Fiber

Data centers will use dark fiber optic cables to save on costs, improve latency, and provide redundancy. First, dark fiber optic cables are already installed into the ground, so data centers who won’t have to worry about paying for installation costs. Speed is also crucial for data centers to efficiently operate, so dark fiber optic cables improve the latency and performance of the connection. 

Lastly, dark fiber provides an additional layer of physical redundancy for the existing systems. Many enterprise customers will have a primary and secondary Internet circuit for redundancy purposes. In the case of a natural disaster or accidents, they could simultaneously lose both the primary connectivity and backup. By running their own fiber links, they could lose their Internet carrier and still run on a private dark fiber network. 

Server Racks, Cabinets, and Accessories

If you’re looking for additional server rack or rack accessories to buy for your data center, feel free to contact us. RackSolutions provides a variety of server racks, colocation cabinets, hypershelves, and rack accessories that are ready to order. With our high-quality, in house manufacturing, you can be confident that you are buying the best rack possible for your data center!  

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 What is Dark Fiber and How Does It Work
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What is Dark Fiber and How Does It Work
dark fiber is ideal for businesses that need control of their network infrastructure and require near zero response times for point to point communication. With a dark fiber network, the operator will act as their own ISP and avoid service delays. The benefits of dark fiber include scalability, network latency, security, and reliability. 
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