[c-nsp] understanding "shape average" option in IOS nested policy-maps

[Martin T]

Hi,

using policy-map "SHAPER-OUTGOING-TRAFFIC" configured as seen below:

!
policy-map VIDEOCONFERENCE-TRAFFIC
 class VIDEOCONFERENCE-TRAFFIC
  priority 4500
policy-map SHAPER-OUTGOING-TRAFFIC
 class class-default
  shape average 14500000
  service-policy VIDEOCONFERENCE-TRAFFIC
!

..on interface facing the Internet in outgoing direction, I'm able to
upload traffic at 10Mbps in total. I send traffic to "class-default"
traffic class and "VIDEOCONFERENCE-TRAFFIC" traffic class
simultaneously.


If I use policy-map below:

!
policy-map VIDEOCONFERENCE-TRAFFIC
 class VIDEOCONFERENCE-TRAFFIC
  priority 4500
policy-map SHAPER-OUTGOING-TRAFFIC
 class INTERNET-TRAFFIC
  shape average 14500000
  service-policy VIDEOCONFERENCE-TRAFFIC
 class class-default
!

..on interface facing the Internet, I'm able to upload
"INTERNET-TRAFFIC" class traffic at 14.5Mbps. I send traffic to
"INTERNET-TRAFFIC" class, "VIDEOCONFERENCE-TRAFFIC" and
"class-default" traffic class at the same time.


Platform is Cisco 2801 and IOS image is
c2801-advipservicesk9-mz.124-15.T3.bin. Why is "shape average"
subtracted in first example(14500000 - 4500000 = 10Mbps) while it was
not subtracted in second example?



regards,
Martin