IBM SC30-3681-08 manual Support, Default value is none

Using ISDN

Config> n 6
Circuit	config: 6>set net 5
Circuit	config:	6>list all
Base net		= 5

X.31 Support

The ITU Standard X.31 is for transmitting X.25 packets over ISDN. This standard

provides support for X.25 with Unconditional Noti®cation on the ISDN BRI

D-channel.

X.31 is available from service providers in several countries. It gives the router a 9600bps X.25 circuit. Since the D-channel is always present, this condition can be an X.25 PVC or SVC.

An X.31 example is, when a packet handler is provided by the ISDN service provider, the X.25 packets and LAP/B frames (RRs, SABMEs, etc.) will be transmitted and received on the D-channel along with the ISDN signaling (Q931/Q921) messages. The D-channel provides a connection that enables the ISDN user terminal to access the packet handler function within the ISDN by establishing a link layer connection (SAPI=16) to that function which can then be used to support packet communications according to X.25 layer 3 procedures. Maximum frame transfer size is 260 bytes.

Figure 38. X.31 Support

Example:

Config>n 6
Config>set data x25 6
Circuit config: 6>set net 5
Circuit config:	6>list all
Base net	= 5
Note: You should assign an X.25 TEI or specify Auto on the BRI base net. The
default value is none.

626MRS V3.2 Software User's Guide