Glossary

Amplifier: Device that boosts the power of an optical signal. An optical amplifier does this without any conversion of the light into an electrical signal.

Dark Fiber: Dark fiber refers to unused fiber-optic cable. The dark strands can be leased or sold to individuals or other companies who want to establish optical connections among their own locations.

Dense Wavelength-Division Multiplexing (DWDM): A variety of WDM that uses multiple wavelengths (or channels) in the 1550-nanometer region of the infrared spectrum. The wavelengths are closely spaced — usually evenly, on a grid.

Gateway co-location: A node on a network that serves as an entrance to another network.

Hut co-location: A dedicated facility designed with resources which include a secured cage or cabinet, regulated power, dedicated Internet connection, security and support. Co-location facilities offer the customer a secure place to physically house their hardware and equipment as opposed to locating it in their offices or warehouse where the potential for damage is much greater.

Indefeasible Right to Use (IRU): The granting of temporary ownership of a fiber optic cable. IRUs are specified in terms of a certain number of channels of a given bandwidth. An IRU is granted by the company or consortium of companies that built the fiber optic network.

Optical Network: A communications network in which data is transmitted over fiber optic lines as pulses of light.