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Configuring X.25 239
CAUTION
Both ends of the X.25 link must agree on the window size or conflicts can occur.
Configuring Window Modulus
The modulus is the packet counting mechanism for X.25. The command to define the counter
limit is as follows:
Router(config-if)#x25 modulo modulus
The value specified using this command dictates the number of packets that can be sent before
the counter must reset. The default value of 8 is widely used and enables seven packets to be
sent (0 isn't a packet, but 1­7 are packets). The only other valid value is 128. However, a
modulo of 128 is quite rare except in cases involving satellite communications.
CAUTION
Both ends of the X.25 link must agree on the window modulus or conflicts can occur.
X.25 Final Configuration
Example 8-5 illustrates the full X.25 configuration, including optional parameters.
Example 8-5
X.25 Configuration with Optional Parameters
RouterA(config)#interface ethernet 0
RouterA(config-if)#ip address 10.1.10.1 255.255.255.0
RouterA(config-if)#interface serial 0
RouterA(config-if)#encapuslation x25
RouterA(config-if)#ip address 10.1.11.1 255.255.255.0
RouterA(config-if)#x25 address 42495092091
RouterA(config-if)#x25 pvc 2 ip 10.1.11.2 51472092091 broadcast
RouterA(config-if)#x25 pvc 5 ip 10.1.11.3 51171092091 broadcast
RouterA(config-if)#x25 ltc 10
RouterA(config-if)#x25 htc 100
RouterA(config-if)#x25 ips 256
RouterA(config-if)#x25 ops 256
RouterA(config-if)#x25 win 7
RouterA(config-if)#x25 wout 7
RouterA(config-if)#x25 modulo 8