Cisco – Monitor specific traffic type on a Cisco router

What you describe would be something like this:

class-map match-all Printer
 match access-group name Printer
!
policy-map WAN-OUT
 class Printer
  shape average 1000000
 class class-default
  fair-queue
  random-detect
!
int WAN
  service-policy output WAN-OUT
!
ip access-list extended Printer
 permit ip any 192.0.2.0 0.0.0.255

This would match traffic going to 192.0.2/24 and shape it to 1Mbps. However I don't think this is necessarily what you want, what if there is no other demand to the circuit, wouldn't you want print job to get full capacity at that time?

Maybe classify traffic in 3 classes, like

1. Important
2. Normal
3. Scavanger

Configuration could be something like:

class-map match-any Important
 match access-group name Important
 match precedence 4  5  6  7 
 match precedence 1  2  3 
class-map match-any Normal
 match precedence 0 
 match access-group name Normal
class-map match-any Scavanger
 match access-group name Scavanger
!
class-map match-all QOS5
 match qos-group 5
class-map match-all QOS3
 match qos-group 3
class-map match-all QOS0
 match qos-group 0
!
policy-map LAN-IN
 class Scavanger
  set qos-group 0
 class Important
  set qos-group 5
 class Normal
  set qos-group 3
!
policy-map WAN-OUT
 class QOS5
  priority percent 80
 class QOS3
  bandwidth percent 20 
 class QOS0
!
int LAN
  service-policy input LAN-IN
int WAN
  service-policy output WAN-OUT
!

Now in LAN ingress we match on traffic and give it internal qos-group 5, 3, 0, these numbers are insignificant they could be anything, it's just way to differentiate the traffic without mangling the existing CoS/PREC/DSCP bits.

After we've marked the traffic in LAN ingress, on WAN egress we match on the earlier defined qos-groups and treat traffic differently.

Here we give Important traffic 80% low-latency privilege to the capacity. For Normal traffic we give 20% contract, so if Important traffic sends 100% and you start to send Normal traffic, 20% of Important traffic would be dropped in favor of letting some Normal traffic pass. We give no contractual capacity to Scavanger class, it'll only send if either Important or Normal class are using less than contractual capacity.

I would suggest creating a static route to Null 0 on the external router:

ip route 192.168.0.0 255.255.248.0 Null 0

• Static route to Null interface is seen as a connected interface on the local router.
  
  Then advertise the summary address in whatever routing protocol is originating the routes with a network statement in the routing process.

When you redistribute from one routing process to the other the summary route should be injected into the OSPF process.

You could also filter out the subnets with a prefix list or route map to be sure the smaller subnets don't get injected.

Hopefully this helps.