
supports many different communication protocols and two analog adapters, each of these ports can be assigned to an ISDN number using the following command:
AT&ZIn=s (where ‘s’ is the MSN)
&ZI0=s | Assigns MSN ’s’, phone number for X.75. |
&ZI1=s | Assigns MSN ’s’, phone number for V.110. |
&ZI2=s | Assigns MSN ’s’, phone number for V.120. |
&ZI3=s | Assigns MSN ’s’, phone number for PPP, MPPP. |
&ZI4=s | Assigns MSN ’s’ for ISDN data, protocol auto- |
| detection. |
&ZI6=s | Assigns MSN ’s’, phone number for Phone 2 (omni.net). |
&ZI7=s | Assigns MSN ’s’, phone number for Phone 1 |
AT&ZI? can be used to display the MSN numbers. The factory default for these numbers are UNASSIGNED.
If an incoming SETUP message is offered with addressing information (i.e. the appropriate part of the called_party_number), this address will be compared with the MSN numbers assigned by the AT&ZIn=s commands. The call will be accepted using the specific protocol, if the assigned number of this protocol matches the received called party number.
ONOTE: You are not required to enter the complete number string for the AT&ZIn command. The last few distinguishable digits will be enough for the TA to make the decision. Two phone number strings are said to be matched if their least significant “n”digit(s) are identical, where “n”is the number of digits in the shorter string.
Called_Party_Subaddress information within the incoming SETUP message can also be used to select the protocols and/or analog ports. In normal conditions Called_Party_Subaddress information is not used by the TA to select the protocols or services, but only indicates the subaddress (if any) to the DTE. Refer to Chapter 12 for more detailed information.
32 ISDN Communication Basics