ZyXEL Communications omni.net LCD+M V.120 Outgoing Protocol

Technical Reference for ZyXEL omni.net series

V.120 Outgoing Protocol

Some switches transmit all network signals through the D-channel (out-of-band signaling), allowing both B-channels to be used exclusively for your communication purposes. This allows for throughput of 64Kbps per channel. However, not all switches support out-of-band signaling at this time. For switches that do not support out-of-band signaling, network signals are transmitted through the B-channels. This reduces the bandwidth to 56Kbps.

When you are making a V.120 call, make sure that the communication supports out-of-band signaling. If it does not support out-of-band signaling, you will need to set your omni.net to 56K mode using the [AT&E1] command ([AT&E0] to set it back to 64k mode.) If your ISDN TA is on the receiving end, you can keep the setting at AT&E0, 64k data mode. The omni.net will automatically switch between the two speeds in answer mode.

	Type AT		Description	omni.net Response
	Command
ATB20<Enter>		Select V.120 for communication.		OK
AT&E0<Enter>		Select 64K data mode.		OK
AT&E1<Enter>		Select 56K data mode.		OK

Now you are ready to dial the phone number. If you need to save the setting into non-volatile RAM, issue the following commands:

AT&W0<Enter>	Save the settings to profile 0	OK
	[Profiles available: 0-3]
ATZ0<Enter>	Save stored settings as the power on
	settings to profile 0. [Profiles available:	OK
	0-3]

All the above commands can be simplified by combining all of the commands onto one line as follows:

&AT&B20&E1&WZ0<Enter>

Finally, use the [ATDIn] command to make the call ('n' is the phone number you wish to dial). Once the connection is made, you should see the following connect message.

ATDIn	CONNECT 115200/V120 56000/LAPD
	This indicates that the connection is made with:
	) DTE speed of 115,200bps.
	) V.120 Protocol
	) Data Speed of 56,000bps.
	) Error Control LAPD.
	Table 45. V.120 Outgoing Protocol

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