Bandwidth Sharing in Cisco Routers

The following example polices the inside interface to 30Mbps.  It also utilizes a fair queue mechanism so that all subnets are queued equally yet can use the entire purchased rate in the absence of competing traffic.

access-list 101 permit ip any a.a.a.a w.w.w.w ## Subnet A

access-list 102 permit ip any b.b.b.b w.w.w.w ## Subnet B

access-list 103 permit ip any c.c.c.c w.w.w.w ## Subnet C

class-map subnet-a
match access-group 101

class-map subnet-b 
match access-group 102

class-map subnet-c
match access-group 103

policy-map subnets
class-map subnet-a
  bandwidth percent 33
class-map subnet-b
  bandwidth percent 33
class-map subnet-c
  bandwidth percent 33
exit

policy-map physical
class class-default
  police 30000000 conform-action transmit exceed-action drop
  service-policy subnets
exit

int fa0/1
service-policy output physical
exit