AI2524 Router Card User’s Manual
Page 12-2 August 1997
2524UM
Note: If you connect a router to an X.25 network, use the
parameters set by your network administrator for th
connection; these parameters will typically be thos
described in the Configure Interface and Modify LAPB
Protocol Parameters sections. Also, note that the X.25
Level 2 parameters described in the Modify LAPB
Protocol Parameters section affect X.25 Level 3
operations.
Configure Interface To configure an X.25 interface, perform these tasks:
zSet the X.25 Mode
zSet the Virtual Circuit Ranges
zSet the Packet Numbering Modulo
zSet the X.121 Address
zSet the Default Flow Control Values
These tasks describe the parameters that are essential for correct X.25
behavior. The first task is re quired. The others migh t be required or op-
tional, depending on what the router is expected to do and on the X.25
network.
Set the X.25 Mode
A router using X.25 Level 3 encapsulation can:
zAct as a DTE or DCE protocol device (according to the needs of
your X.25 service supplier)
zUse the Internet Engineering Task Force (IETF) standard encap-
sulation, as specified by RFC 1356.
Because the default serial encapsulation is High-level Data Link Con-
trol (HDLC), you must explicitly configure an X.25 encapsulation
method.
In interface configuration mode, configure th e mode of operation and
one of these encapsulation types for a specified interface:
encapsulation x25 [dte | dce] [ietf]]
Typically, a Public Data Network (PDN) will require attachment as
DTE. This requirement is distinct from the hardware interface DTE or
DCE identity.
The default mode of operation is DTE, and the default encapsulation
method is Cisco's pre-IETF method.