Modulation in which (a) an audio frequency band is split into two sub-bands, i.e., a higher and a lower band, and (b) the signals in each sub-band are encoded using ADPCM.

[An] Individual with primary responsibility for managing the distinguished name process. [INFOSEC-99]

[A] major subdivision of an assembly consisting of a package of parts, elements, and circuits that perform a specific function. [INFOSEC-99]

A carrier used to modulate another carrier.
Note: The modulated carrier can be used to modulate another carrier, and so on, so that there can be several levels of subcarriers, i.e., several intermediate carriers.

A class derived from another class by specialization. [T1.260-1998]

1. In cryptography, an entity whose public key is certified in a public key certificate.
2. Generally, a person, process, or device, causing information to flow among objects or change to the system state. [INFOSEC-99]
3. An active entity, generally in the form of a person, process, executing program or device that causes information to flow among objects or changes… (Read More →)

An authority recognized in a Security Domain as a trusted source of security information concerning security subjects (human beings and Applications) [ECMA138].

Sensitivity label(s) of the objects to which the subject has both read and write access. Security level of a subject must always be dominated by the clearance level of the user associated with the subject. [INFOSEC-99]

1. In a layered open communications system, a specified subset of the services, functions, and protocols included in a given layer.
2. In the Open Systems Interconnection--Reference Model, a subdivision of a given layer, e.g., a conceptually complete group of the services, functions, and protocols included in the given layer.

In an Internet Protocol (IP) address, an extension that allows users in a network to use a single IP network address for multiple physical subnetworks.
Note: The IP address contains three parts: the network, the subnet, and host addresses. Inside the subnetwork, gateways and hosts divide the local portion of the IP address into a subnet address and a host… (Read More →)