Considering Going to the Dark Side? The Hidden Costs of Dark Fiber

Remember “dark fiber?” Well it’s back.

Quick history lesson for those not familiar with this telecom buzz word. Dark fiber was a hot topic during the dot-com days of the late 1990’s. Telecoms, railroads and other large utilities planned for growth and increased demand of their optical fiber networks by laying down extra, unlit fiber cables. When the bubble burst and advancements such as Wavelength Division Multiplexing (WDM) allowed carriers to get more out of their existing lit cables, network owners began selling off their unused optical networks – thus the term “dark” fiber.

Now dark fiber is back in the vernacular mostly sparked by Google, Amazon.com and Microsoft buying up large amounts of the unlit optic cable for their expansion into cloud computing. However, we’ve seen another trend bringing dark fiber back into the mainstream — recent large-scale implementations of purchased dark fiber in the education and government spaces.

Driven by a variety of government programs targeted to “bridge the digital divide” which allows some government funds to be used for dark fiber, many entities (state agencies, higher ed organizations, etc) are looking at dark fiber as an option to bring broadband to their constituents.

It’s no surprise when you consider two of the most compelling benefits: nearly unlimited bandwidth and full ownership (and thus control) of the network.

While dark fiber has many upsides, there can be some “hidden” costs. Here are some things to consider before jumping in:

1)    Start up costs: Have you considered the operational execution and costs of “flipping the switch”? Operationally, you’ll need to create processes such as provisioning and trouble ticketing. In addition, you’ll have CapEx due to equipment needed including optical amplifiers, network management tools and transceivers.

2)    Long term/sustainability – A network doesn’t run itself. Once you get it up and running, you should consider the personnel costs of operating and maintaining the network. Does your staff have the expertise and bandwidth to maintain your network? Do they have the expertise in provisioning and managing traffic to ensure QoS? How will you respond to failures, capacity increases and bandwidth shaping? Also, all that equipment you needed to get started – a seemingly “one-time” cost – will require refreshes (typically every 3 – 6 years).

The bottom-line is that, on the surface, dark fiber may seem like a slam dunk, but the start-up and long-term costs should be considered before making a move.

What’s your take? Is dark fiber worth it?

Comments (7)

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  1. Andy Forsyth

    My experience shows that unless you are a carrier and are staffed to support the variables you mentioned it’s not worth it for an enterprise customer to try to light and manage DF. Revenue streams carriers can associate with purchasing and lighting DF make proving in the cost to aquire and manage those assets much more reasonable.

  2. Jim

    Getting into DF is not for the faint of heart, but it makes sense if you are at a certain size. Most cities are not big enough, but a Google or other similarily sized firm is big enough. I think the point you miss is you do not have to operate the network for profit and whatever you do shift to your DF is going to result in a net savings to you relative to spending with a carrier. The issue is you need to get to a specific size to make it work successfully.
    Point 1: Start up Costs – c’mon, saying you have to buy into the infrastructure goes without saying. This is no different to many other similar activities large enterprise firms take on. It is something to be embraced, not feared. If you cannot come up with $500M in CapEx then you should not be in this game.
    Point 2: This is really the same as point 1. you are saying beware the operating costs of operating a network.

    Many of the issues the carriers face in trying to fit more traffic over the same lines in order to generate profits are not faced by firms buying and operating DF. And it goes without saying that an intellegent operating firm will plan on an appropriate equipment lifecycle that makes sense for their business. Many of the costs do not translate over to private firms as they increase profitability by not paying for carrier services. Again this assumes you know how to operate a carrier efficently, and again I would embrace it, not be fearful of it.

  3. David Hunter

    Another challenge that end customers should be aware of with managing their own “dark fiber” is the element of resolving unpredictable outages such as cable cuts and and other issues. This in many cases requires a customer to be ready to issue a “blank check” to resolve the outage which is almost impossible to manage with their current budget situations.

  4. There’s no need for fibre – a Canadian/UK company has recently demonstrated in Cambridge, UK that they can deliver up to 400 Mbps over existing rural copper telephone networks.

  5. Mark Settle

    David, it depends who you work with. A good dark fiber provider has an SLA that includes things like network repair. You’d still be responsible if you did the cutting of the wire, but that’s true of any fiber, not just dark fiber.

  6. Do you want dark fiber? It is often the best option. Zayo provides it in dozens of markets across the U.S. Contact us!!!