Kbps - A transmission speed. Kilobits (thousands of bits) per second.
Kilobyte (KB) - 1,024 bytes

L-Band - In electrical systems, portion of the radio frequency spectrum, 950 MHz to 2050 MHz, used in satellite, microwave and GPS applications. In optical systems, the range of wavelengths between 1570nm and 1620nm.
Laser - A device which produces a single frequency of light.
Light Emitting Diode (LED) - An LED is a semiconductor light source that emits light in the optical frequency band or the infrared frequency band. LEDs are a major light source for optical fiber transmission used with multimode optical fiber in applications that require a low-cost light source.
Lightguide - An extremely clear, thin glass fiber that is to light what copper wire is to electricity. Synonymous with optical fiber.
Lightwave - Particles of light known as photons travel in waves. The length of the waves determines the light's color, speed, and behavior in a lightguide.
Local Area Network - A LAN is a network in which two or more computers, located within a limited distance of one another, are connected in order to share files and resources. A PC-based LAN consists of a dedicated server running a network operating system and attached to several workstations. A host-based LAN consists of one or more hosts and terminals. Examples of LAN architectures are Ethernet, ARCnet, fiber distributed data interface (FDDI), and token ring.
Local Exchange Carrier - An organization that provides local telephone service, which includes the RBOCs, large companies such as GTE and hundreds of small, rural telephone companies. A LEC controls the service from its central office (CO) to subscribers within a local geographic area.
Local Loop - The physical wires that run from the subscriber's telephone set, PBX, or key telephone system, to the telephone company central office. Increasingly, the local loop now goes from the main distribution frame in the basement to the telephone company. And the subscriber is responsible for getting his wires from the box in the basement to his phone, PBX, or key system.