3Com 10014299 manual By default, DSS1 signaling is used on Isdn PRI interfaces

190 CHAPTER 15: CONFIGURING ISDN PROTOCOL

■ Set the called number or sub-address to be checked in digital incoming call

1 Configure ISDN Signaling Type

Perform the following configurations in either system view or interface view.

Table 220 Configure type of signaling on ISDN interface

Operation	Command
Set ISDN signaling to QSIG	isdn	protocol-type qsig
Set ISDN signaling to DSS1 (Digital Subscriber	isdn	protocol-type dss1-
Signaling No.1)

By default, DSS1 signaling is used on ISDN PRI interfaces.

The isdn protocol-typecommand can take effect only on ISDN PRI interfaces. For an ISDN BRI interface, it does not take effect. In other words, an ISDN BRI interface can use only DSS1 signaling, whereas an ISDN PRI interface can use either DSS1 signaling or QSIG signaling.

Using the isdn protocol-typecommand in system view will not affect the existing ISDN PRI interface, and it will only change the default type of signaling on the newly created ISDN PRI interface.

2 Configure the QSIG Signaling Parameters

If QSIG signaling is used on an ISDN PRI interface, you can configure the QSIG signaling parameters. The following configuration commands can be used only when the ISDN PRI interface adopts QSIG signaling.

a Length of call reference

Call reference is the flag used to distinguish the communication entities. A call reference uniquely identifies a call.

Perform the following configurations in interface view.

Table 221 Configure the length of call reference

Operation	Command
Set the length of call reference to 1 byte	isdn	crlength 1
Set the length of call reference to 2 bytes	isdn	crlength 2

By default, the length of call reference is two bytes.

bMode in which a called number is received

A router can receive called numbers in two modes: overlap receiving and complete receiving. You can set the receiving mode on the router according to the transmitting mode on the peer.

Perform the following configurations in interface view.

Table 222 Configure the receiving mode

Operation	Command
Overlap receiving mode is used.	isdn overlap-receiving
Complete receiving mode is used.	undo isdn overlap-receiving

By default, ISDN PRI interfaces receive called numbers in overlap receiving mode.

cMode in which a called number is sent