VSAT Static IP Binding

Hello,

i want to bind my 2 static ips in Mikrotik

1] My UpLINK [ DSL ] 172.16.1.x
2] My Downlink [ VSat ] 192.168.238.x

i want to Bind my DSL ip into VSAT ip so that my whole Internet Services Shift from my dsl to my VSAT ip.

like if i connect pppoe my ip need to be 192.168.238.x rather 172.16.1.x


Regards

Rizwan