ADTRAN 1200051L6 - Manual (Page 45)

Chapter 6. Configuration
61200051L1-1D ISU 2x64 Dual Port ISDN Service Unit User Manual 31
Setting the Call Type
Call type is configured for both DTE#1 and DTE#2. When using
the front panel, select the appropriate DTE with either arrow key
and press Enter. When using a VT 100 terminal, select the option
number corresponding to the appropriate DTE and press Return.
The Call type can be configured four different ways, depending
on the type of service used: Speech , Audio, Data 56 kbps, or
Data 64 kbps.
Speech
Speech directs the call control software to request a Mu-law (or
A-law) speech circuit as the bearer capability for outgoing calls.
The Speech option is used with an ISDN line configured for voice
service. In some areas voice service is less expensive than data
service. A Speech call type does not guarantee an end-to-end
digital connection with some local and long distance carriers.
Audio
Audio directs the call control software to request a 3.1 kHz audio
circuit as the bearer capability for outgoing calls. The Audio
option is used with an ISDN line configured for voice service. In
some areas audio service is less expensive than data service.
Selecting Audio guarantees a digital end-to-end ISDN connec-
tion.
Data 56kbps
Data 56kbps directs the call control software to request a 64 kbps
data circuit that is rate-adapted to 56 kbps. Data 56 kbps is
intended for use in circumstances where interoperability with
Switched-56 service is desired.
Data 64kbps
The default Call type for ISDN service is Data 64 kbps. This
directs the call control software to request an unrestricted 64 kbps
circuit.