Technical Reference for ZyXEL omni.net series

About V.110, V.120 and X.75 ISDN Protocols

 

ISDN Protocols

 

 

Description

 

V.110

 

 

V.110 is most popular in Japan.

 

 

 

 

 

 

V.120

 

 

V.120 is most commonly used in the U.S.A.

 

 

 

 

 

 

X.75

 

 

X.75 was originally designed for packet-switched signaling systems in public networks

 

 

 

 

 

to provide data transmission services. However, it is now also used as the link layer for

 

 

 

 

 

telematic services (as defined in T.90) in ISDN. These services include both ISDN

 

 

 

 

 

circuit-switched mode (DTE-DTE communication) and ISDN packet-switched mode

 

 

 

 

 

(DTE-DCE communication).

 

Table 43. Description of V.110, V.120 and X.75 ISDN Protocols

Answering V.110, V.120, and X.75 Calls

In most cases, there is no need to configure the ISDN mode to the protocol of an incoming call. Your omni.net is able to determine the correct protocol to use by examining the data coming in from the remote site if the device is set to auto-answer or once an answer command is issued.

To allow your ISDN TA to auto-answer the incoming call, you need to set [S0] to a value greater than or equal to 1 (i.e. ATS0￿1). If [S0] is not set (S0=0), the DCE will report "RING" to your terminal, and also make an audible ring notification.

Placing V.110, V.120, and X.75 Outgoing Calls

The following tables describe the [ATB] commands used to specify the outgoing protocol.

8-2