Why some ADSL line use dialer interface and other use ATM subinterface for connection?

[jiakeai1999]

Hi, Why some ADSL line use dialer interface and other use ATM subinterface for connection? 

interface ATM0.1 point-to-point
ip address 220.x.x.x 255.255.255.252
ip access-group 100 in
ip virtual-reassembly
ip tcp adjust-mss 1452
no snmp trap link-status
pvc 8/35
encapsulation aal5snap

thanks 

[Amit Goyal]

Hi,

It depends upon the encapsulation used by ISP. if they are providing you internet services over plan ATM interface then you don't need a dialer interface. But if ISP is providing services via PPPOA then you need dialer interface.

HTH

-Amit