General Service Subscription Management

GPON Transmission Convergence layer

In computer security, a functional unit that provides a security filter between two data processing systems operating at different security levels or between a user terminal and a database to filter out data that the user is not authorized to access. [2382-pt.8]

See frequency guard band, time guard band.

A transmission frequency that is not to be jammed or interfered with because of the value of the information being derived from it.
Note: For example, a guarded frequency will not be jammed when the tactical, strategic, and technical information that can be obtained from the transmissions outweighs the potential operational gain achieved by jamming. [From Weik '89]

Graphical User Interface

Global Unique Identifier

Synonym bound mode.

In an optical fiber, a ray that is confined primarily to the core.
Note: A guided ray satisfies the relation given by ,f21 where r is the angle the ray makes with the fiber axis, r is the radial position, i.e., radial distance, of the ray from the fiber axis, nr is the refractive index at the radial distance r… (Read More →)

A wave having (a) energy concentrated near a boundary, or between substantially parallel boundaries, separating materials of different properties and (b) a direction of propagation effectively parallel to these boundaries.