bridging irb

interface bvi 1
ip address 172.16.1.1 255.255.255.252

Interface Multilink1
no ip address
ppp multilink
ppp multilink group 1
bridge-group 1

interface serial0/0
no ip address
encapsulation ppp
ppp multilink
ppp multilink group 1

interface serial1/0
no ip address
encapsulation ppp
ppp multilink
ppp multilink group 1

int FastEthernet0/0
ip address 192.168.1.153 255.255.255.0
bridge-group 1
bridge-group 1 spanning-disabled