C-1
Appendix
C
Glossary
This appendix provides brief definitions of terms used in the guide.
Bold
items in the text indicates
that the item is defined in the list.
A
A--law
law
An encoding scheme that determines how an analog speech signal is converted to a digital signal.
A-law encoding is used in Europe. The other algorithm,
U-law
, is used in North America and Ja-
pan.
A
Alias
lias
A name given to each host to distinguish it from one another within an
H.323
network. While us-
ing the same Internet address, each host name can be set differently.
Automatic Number Identification
Automatic Number Identification ((ANI
ANI))
ANI enables call recipients to recognize a caller’s telephone number. How this works varies from
provider to provider. This service is often provided by sending DTMF tones with a call.
Channel
Channel
A channel through a device, controlling data delivery between two devices, for information deliv-
ery. As the channel is a logical connection channel rather than a physical one connecting devices, a
number of logical channels can exist even through only one physical communication line is pre-
sent.
CODEC
CODEC ((COder
COder--DECoder
DECoder))
Converts analog voice to digital bit stream, and digital bit stream to analog voice. It can be also re-
ferred to as a type of compression (e.g.
G.729
CODEC).
Delay Start
Delay Start
A trunk signal method. A call is initiated when the trunk is seized at the sending end. The Off
Hook status of the PBX at the receiving end lasts until it becomes ready to receive call data. Once
it is ready to receive, it is changed to On-Hook status. When the PBX at the sending end sends call
data, the PBX at the receiving end receives it and calls the subscriber at the receiving end. When
