This is the first of two entries on dark fiber arrangements for the dedicated, high-bandwidth requirements of businesses, medical and educational institutions, and state and local governments (collectively “enterprises”).

Enterprises should consider dark fiber arrangements for local and regional high capacity requirements. High-bandwidth, dedicated services (Gig-Ethernet and higher) within metropolitan areas are relatively expensive on a cost-per-mbps basis; special access service rates are not competitive and the major carriers are not aggressively competing for dedicated high capacity services in regional markets.

The second entry focuses on the two principal agreements under which enterprises may acquire dark fiber: indefeasible rights of use (“IRUs”) and leases.

Dark Fiber—In Brief

Dark fiber is a facility, comprised of glass fibers, placed in a loose tube with filler and strength members; multiple tubes may be placed within a sheath (collectively “fiber optic cable.”)  The unlit glass fibers are universally referred to as “the dark fibers.” The “fiber counts” in a fiber optic cable vary. Fiber optic cable may be installed in underground conduit (“underground”) or extended along utility poles and other aboveground infrastructure (“aerial”). Most dark fiber arrangements are between dark fiber providers and telecommunications carriers.

In dark fiber arrangements, the customer (carrier or end-user) is responsible for “lighting the fiber”—installing and maintaining the electronics, principally the transmitters to convert electrical signals into light and the receivers that convert the light back into electrical signals for processing and conveying communications. A dark fiber provider terminates its fiber optic cable in connectors or performs fiber splices between their dark fibers and its customer’s cabling or fiber at mutually agreed upon demarcation points (patch panels that may contain connectors or splice boxes or both).

Dark fiber customers typically do not physically access the dark fibers, but often require providers to perform tests to confirm the glass fibers meet end-to-end connectivity measures and that all splices connecting network fiber to the customers’ cables meet industry standards at delivery (acceptance) and that these measures and standards are maintained for the duration of the agreed upon term.

The Merits of Dark Fiber Connectivity

                  Dark Fiber is a Durable Asset. Fiber optic cables have useful lives of 20–30 years, or more.  Fiber optic technology (the cable and the electronics) is a building block of telecommunications networks throughout the world; wireless and wireline. Annual maintenance costs are modest, though fiber cuts do occur and permanent restoration is a significant undertaking that dark fiber providers price into their charges.

Derivable Bandwidth Will Increase Over Time. The electronics that “light” the dark fibers are part of a very large, well-funded technology ecosystem. Over the useful life of a fiber optic cable, the derivable bandwidth/capacity should increase substantially due to advances in the underlying technologies embedded in the electronics. This is why one major wireless carrier opts for dark fiber connectivity between its small cell sites and network.

Fiber Deployments Are Capital-Intensive. The “sunk costs” of fiber networks are substantial: right-of-way and easement acquisition, construction and other land use permitting, the installation of the fiber optic cable—underground or aerial, the fiber optic cable, and the splicing and testing of the fiber. Splicing is necessary throughout a fiber network because cable lengths are limited by amount of cable that can be rolled around spools for transport and ready deployment. Regenerators must also be installed in fiber networks as the signal must be regenerated to reach distant endpoints.

For these reasons, enterprise customers and technology companies rarely construct fiber networks extending beyond the contiguous real estate of their facilities. The major exceptions are electric utilities that have deployed fiber optic networks for years to support their operations. Utility easements and rights-of-way typically accommodate dark fiber installed for a utility’s internal telecommunications requirements.

Major Telecommunications Carriers Typically Do Not Offer Dark Fiber Arrangements. The three largest domestic wireline carriers: AT&T, Verizon and CenturyLink do not typically offer, if at all, dark fiber options to end user customers. It is doubtful this practice will change significantly despite Verizon’s acquisition of XO Communications and CenturyLink’s proposed acquisition of Level 3 Communications. The three largest cable operators—Comcast, Charter-Time Warner and Cox may prove more flexible.

Zayo is probably the largest, independent (as of the date of posting for this entry at least) dark fiber provider (that also offers services) in the United States. There are other metro-area fiber networks in the larger metropolitan areas. Service providers offering dark fiber arrangements exist in less densely populated areas as well, particularly along the Nation’s major North-South and East-West fiber routes.

Total Cost of Ownership. The full cost of dark fiber arrangements includes the cost of the electronics, the lease/use charges for the dark fibers, the dark provider’s one-time costs particularly extending facilities to a customer’s locations, and the customer’s costs in managing the electronics and monitoring network connectivity. On the other hand, the USF charges are not imposed on dark fiber transactions and sales, use and gross receipts taxes applicable to “telecommunications services” may not apply though other state taxes may apply (to be confirmed by state transaction tax counsel).