J

Jitter
A signal or image distortion caused by poorly synchronized signal transmission. Also, a flickering monitor display caused by a bad connection, hardware malfunction, or incorrect refresh rate.

K

No Glossary Terms

L

LAN
A LAN is a grouping of computers via a network, typically confined to a single building or floor of a building.

Light Emitting Diode (LED)
LED is an electronic component that emits light when an electrical signal flows through the component. LEDs are used, for example, to indicate network activity for a networking device such as a hub, or as a light source for fiber optic cable (multimode) implementations.

Lobe
A lobe is a single loop, or station, of a Token Ring network. A Token Ring network can contain many individual lobes. A lobe wire connects a Token Ring station to the MAU.

Local Exchange Carrier (LEC)
See below.

Local Exchange Carrier
A local exchange or central office (CO) is a telephone company facility where local loops are terminated. The function of a CO is to connect individual telephones through a series of switches. COs are tied together in a hierarchy for efficiency in switching. Other terms for CO are wiring center, and public exchange.

Local Loop
A local loop is a span of copper cabling that exists between a telephone subscriber and the closest telephone office (local exchange).

Logical Link Control
LLC is the upper layer of the 802 LAN protocol suite, as defined by the IEEE 802.2 standard.