ICHT
Issue 1.0 May 2003
409
H12
An ISDN information transfer rate for 1920-kbps data defined by CCITT and ANSI
standards.
handshaking logic
A format used to initiate a data connection between two data module devices.
hertz (Hz)
A unit of frequency equal to one cycle per second.
high-reliability system
A system having the following: two control carriers, duplicate expansion interface
(EI) circuit packs in the PPN (in R5r with CSS), and duplicate switch node clock
circuit packs in the switch node (SN) carriers. See also
duplicated common
control
on page 403,
duplication
on page 403,
duplication option
on page 403, and
critical-reliability system
on page 398.
HNPA
See
home numbering-plan area code (HNPA)
on page 409.
holding time
The total length of time in minutes and seconds that a facility is used during a call.
home numbering-plan
area code (HNPA)
The local area code. The area code does not have to be dialed to call numbers
within the local geographical area.
hop
Nondirect communication between two switch communications interfaces (SCI)
where the SCI message passes automatically without intermediate processing
through one or more intermediate SCIs.
host computer
A computer, connected to a network, that processes data from data-entry devices.
hunt group
A group of extensions that are assigned the Station Hunting feature so that a call to a
busy extension reroutes to an idle extension in the group. See also
ACD work
mode
on page 386.
Hz
See
hertz (Hz)
on page 409.
I1
The first information channel of DCP.
I2
The second information channel of DCP.
IAS
Inter-PBX Attendant Service
ICC
Intercabinet cable or intercarrier cable
ICD
Inbound Call Director
ICDOS
International Customer-Dialed Operator Service
ICHT
Incoming call-handling table
