3com 3031 Instruccion De Instalación

Subinterface

185

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X.25 address map different from that of the WAN interface (also called the
main interface) to which the subinterface belongs

■

IP address beyond the segment on which the main interface is located

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IPX network number and other IPX parameters different from the main
interface

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VC belonging to the subinterface

For more information about the configurations, refer to Part IV “Link Layer
Protocol” and Part V “Network Protocol”.

Typical WAN subinterface configuration example

1 Networking requirements

As shown in the following figure, the WAN interface Serial0/0/0 on Router A is
connected to Router B and Router C via a public FR network. By configuring
subinterfaces on Serial0/0/0 on Router A, you can make LAN 1 to simultaneously
access LAN 2 and LAN 3 via Serial0/0/0.

Figure 33 Networking for the WAN subinterface configuration example

2 Configuration procedure

a Enter the view of Serial0/0/0 on Router A.

[3Com]interface serial 0/0/0

b Encapsulate the interface with FR.

[3Com-Serial0/0/0]link-protocol fr

c Specify the interface to work as DTE in FR.

[3Com-Serial0/0/0]fr interface-type dte

d Create the subinterface Serial 0/0/0.1 on Serial0/0/0 on Router A, specify it

work in point-to-point mode, and enter the view of the subinterface.

[3Com]interface serial 0/0/0.1 p2p

e Assign the IP address 202.38.160.1 to the subinterface, given the mask is

255.255.255.0.

[3Com-Serial0/0/0.1]ip address 202.38.160.1 255.255.255.0

Router A

Router B

Router C

Frame Relay

Ethernet 3

Ethernet 2

Serial0

DLCI=50

DLCI=60

DLCI=70

DLCI=80

202.38.160.1

202.38.160.2

202.38.161.1

202.38.161.2

129.9.0.0

129.10.0.0

129.11.0.0