Search Keyword By: H
H-channel
In Integrated Services Digital Networks (ISDN), a 384-kb/s, 1472-kb/s, or 1536-kb/s channel, designated as “H0“, “H10“, and “H11“, respectively, accompanied by timing signals used to carry a wide variety of user information. Note: Examples of types of user information representation forms include fast facsimile, video, high-speed data, high-quality audio, packet-switched data, bit streams at rates less than the respective H-channel bit rate that have been rate-adapted or multiplexed together, and packet-switched information.
H-plane bend
Synonym H-bend.
H-VPLS
Hierarchical Virtual Private LAN Service
HA
High Availability
hacker
A person who breaks into, or attempts to break into, or use, a computer network or system without authorization , often at random, for personal amusement or gratification, and not necessarily with malicious intent. 2. [An] unauthorized user who attempts to or gains access to an information system (IS). [INFOSEC-99] 3. A technically sophisticated computer expert who intentionally gains unauthorized access to targeted protected resources. [After ANSDIT] 4. Loosely, a computer enthusiast. [ANSDIT] 5. A person who uses a computer resource in a manner for which it is not intended or which is in conflict with the terms of an acceptable-use policy, but (unlike the work of a cracker) is not necessarily malicious in intent.
Hagelbarger code
A convolutional code that enables error bursts to be corrected provided that there are relatively long error-free intervals between the error bursts. Note: In the Hagelbarger code, inserted parity check bits are spread out in time so that an error burst is not likely to affect more than one of the groups in which parity is checked.
half-duplex (HDX) operation
Operation in which communication between two terminals occurs in either direction, but in only one direction at a time. Note: Half-duplex operation may occur on a half-duplex circuit or on a duplex circuit, but it may not occur on a simplex circuit. Synonyms one-way reversible operation, two-way alternate operation.