ADTRAN ISU 128 - Manual (Page 39)

Chapter 6. Configuration
24 ISU 128 User Manual 61202.029L2-1
Figure 6-2
VT 100 Configuration Screen
Switch Protocol
Find out what kind of ISDN switch your local CO is using by asking the tele-
phone administrator or telephone company representative. Configure the ISU
128 for either a Northern Telecom DMS-100
®
, AT&T 5ESS
®
switch, or a switch
conforming to the National ISDN-1 standard (usually an AT&T 5ESS, NTI
DMS-100, or Siemens EWSD). In the Far East, configure for the NEC switch.
Call Type
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.
When placing outgoing calls using the optional V.34 modem, the unit must be op-
tioned for either speech or audio call type.
Speech
Speech directs the call control software to request a Mu-law/A-law speech cir-
cuit 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 costs