Information Technology Reference
In-Depth Information
Table G.6
ISDN network messages
Call establish
Information messages
Call clearing
ALERTING
RESUME
DISCONNECT
CALL PROCEEDING
RESUME ACKNOWLEDGE
RELEASE
CONNECT
RESUME REJECT
RELEASE COMPLETE
CONNECT
ACKNOWLEDGE
SUSPEND
RESTART
PROGRESS
SUSPEND ACKNOWLEDGE
RESTART ACKNOWLEDGE
SETUP
SUSPEND REJECT
SETUP ACKNOWLEDGE
USER INFORMATION
Calling
TE
Network
Called
TE
ALERTING
CONNECT
CONNEC
T
Data flow
Figure G.11
Call establishment and clearing
G.6 Speech sampling
With telephone-quality speech the signal bandwidth is normally limited to 4 kHz, thus it is
sampled at 8 kHz. If each sample is coded with eight bits then the basic bit rate will be:
