3Com 10014299 Configure X.25 Interface, Set/Cancel the X.121 address of the interface, Address

200CHAPTER 16: CONFIGURING LAPB AND X.25

Configure X.25 Interface

The configuration of X.25 interface includes:

■Configure X.121 address

■Configure X.25 working mode

■Configure X.25virtual circuit range

■Configure X.25 modulo

■Configure X.25 default flow control parameter

Only when configured as an X.25 interface, can an interface transmit data with X.25 protocol.

In the following configuration commands, only “Configure X.25 working mode” is mandatory, and other configuration items are optional, depending on the specific condition of X.25 network that is accessed.

1Configure X.121 address

If the 3Com Router series does not originate or terminate calls but only participates in X.25 switching, there is no need to configure an X.121 address. However, if the 3Com Router series is attached to a X.25 Network, you should configure an X.121 address for the interface, and usually, the address is provided by the ISP.

To set/cancel the X.121 address, perform the following task in interface view.

Table 234 Set/Cancel the X.121 address of the interface

Operation	Command
Set the X.121 address of the interface	x25 x121-address
	x.121-address
Cancel the set X.121 address of the interface	undo x25 x121-address

2Configure X.25 working mode

To configure X.25 working mode, perform the following task in the interface view.

Table 235 Set X.25 working mode

Operation	Command
Set the working mode and packet format of X.25	link-protocol x25 [ dte
interface	dce ] [ nonstandard ietf ]

Layer 3 of X.25 supported by 3Com Router series can work in both DTE mode and DCE mode. It can also specify the datagram format among the two optional formats: IETF and Nonstandard.

Note that generally speaking, public X.25 packet switching network requires the router to access at DTE side and requires the IETF format. Therefore, the working mode of X.25 should be DTE and the format should be IETF. If a pair of serial interfaces of two routers is directly connected for data transmission, make sure the two transmission ends are DTE and DCE and the formats are the same.

For X.25 supported by 3Com Router series, default working mode is DTE and default format is IETF.

3Configure X.25 virtual circuit range