Hello Bila

You can set up your Policing QoS on the following

access-list 1 permit ip any 1.1.1.1  Subnet 1

access-list 2 permit ip any 2.2.2.2 Subnet 2

class-map subnet 1

match access-group 1

class-map subnet 2

match access-group 2

policy-map ISP Limit

class subnet 1

  bandwidth [rate]

  police [the rate limit] exceed-action [drop]

class subnet 2

  bandwidth [rate]

  police [the rate limit] exceed-action [drop]

Than you will need to bind it to the output of the interface towards the up stream

interface fastethernet 0/1 " up stream interface

service-policy out ISP Limit

Hope it will help

Ahmed Sonba