Enterasys Networks XSR-3020 - Manual (Page 55)

Configuring the WAN Ports
XSR Getting Started Guide 3-11
ADSL Configuration
ADSL can be configured using three different types of encapsulation: PPPoA, PPPoE, and IPoA.
Continue configuration with the ADSL type of your choice.
PPPoE
The following commands configure a sample PPPoE topology. The first set configures the LAN
interface with directed broadcasts prohibited.
XSR(config)#interface FastEthernet 1
XSR(config-if<F1>)#ip address 192.168.1.1 255.255.255.0
XSR(config-if<F1>)#no ip directed-broadcast
XSR(config-if<F1>)#no shutdown
The commands below configure the ATM interface and sub-interface with a negotiated IP
address, PAP username and password, and ban keepalives. They also reset default PVC VPI and
VCI values to those requested by the DSL provider. Notice that the Maximum Segment Size (MSS)
is set to 1400 bytes for TCP SYN (synchronize) packets. Because a PC connected to a Fast/
GigabitEthernet port may be unable to access Web sites if its MSS setting is too high, subtracting
for the PPPoE, IP, TCP, and GRE headers (6, 20, 20, and 24 bytes, respectively) and the PPP
Protocol ID should avoid that problem.
XSR(config)#interface ATM 0
XSR(config-if<ATM0/0>)#no shutdown
XSR(config-if<ATM0/0>)#interface ATM 0.1
XSR(config-if<ATM0/0.1>)#no shutdown
XSR(config-if<ATM0/0.1>)#encapsulation mux pppoe
XSR(config-if<ATM0/0.1>)#ip address negotiated
XSR(config-if<ATM0/0.1>)#ip mtu 1492
XSR(config-if<ATM0/0.1>)#ip tcp adjust-mss 1400
XSR(config-if<ATM0/0.1>)#ppp pap sent-username user@net password letmein
XSR(config-if<ATM0/0.1>)#no ppp keepalive
XSR(config-if<ATM0/0.1>)#pvc 0/100
The following optional commands configure two default routes:
XSR(config)#ip route 0.0.0.0 0.0.0.0 30.0.0.10
XSR(config)#ip route 30.0.0.10 255.255.255.255 ATM 0.1
The following optional commands configure NAT:
XSR(config)#access-list 99 permit 192.168.1.0 0.0.0.255
XSR(config)#interface FastEthernet 1
XSR(config-if<F1>)#ip nat source list 99 assigned overload
PPPoA
Enter the following commands to configure PPPoA. The first set configures the LAN interface
with directed broadcasts prohibited.
XSR(config)#interface FastEthernet 1
XSR(config-if<F1>)#ip address 192.168.1.1 255.255.255.0
XSR(config-if<F1>)#no ip directed-broadcast
XSR(config-if<F1>)#no shutdown