Cisco Cisco 1800 2800 3800 Series AP-AG 802.11a b g High-Speed WIC

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Mark packets as close to the source as can be trusted to differentiate traffic into sub-classes to be used in

the third level policy. Methods for marking are provided in Cisco best practices QoS guides such as

www.cisco.com/c/en/us/td/docs/solutions/Enterprise/Campus/Borderless_Campus_Network_1-

0/Borderless_Campus_1-0_Design_Guide/BN_Campus_QoS.html#wp1232603

and

www.cisco.com/c/en/us/td/docs/solutions/Enterprise/WAN_and_MAN/QoS_SRND/QoS-SRND-Book.html

Use a CS5/EF class for voice traffic and/or the most critical traffic (second level policy). It is

recommended to set this traffic class to less than or equal to 25% of the service rate (either 0.5Mbps or

2Mbps, i.e. no greater than 125Kbps or 512Kbps). For voice traffic, best practices for call admission

control should be deployed to limit the number of simultaneous calls and ensure sufficieint call quality.

Use a CS3/AF3x/CS4/AF4x class for important data or video applications (second level policy).

The shaped rate for CS3/AF3x/CS4/AF4x class in the second level policy should be set to the service rate

(0.5Mbps or 2Mbps) less the rate defined for the CS5/EF class.

Multiple classes can be defined in the third level policy, providing granular minimum bandwidth to multiple

classes of important traffic (e.g. AF31, AF32, AF33, AF41, AF42, AF43, CS3, CS4).

Notes:

For some deployments with significantly greater than 3Mbps uplink bandwidth, there may be a desire to

use more than 2Mbps for CS3/AF3x/CS4/AF4x traffic. However, that traffic class/bearer will be policed in

the network. There is an option for the 2

level policy to instead of shaping CS3/AF3x/CS4/AF4x traffic,

to use a policer. However the policer on the ISR can be configured to not drop packets exceeding the

service rate, but instead remark DSCP. The packets over the service rate would then be carried in the

default bearer (as best effort). This important but over-contract remarked traffic can still gain better

treatment than traffic with DSCP 0, via the “random-detect dscp-based” treatment defined under “class-

default” in the recommended configurations below. This can be done by remarking the over-contract

important traffic with a DSCP value of CS2 for example. An example of this method: edit the 2

level as

follows:

Replace “shape average 2000000”

with “police 2000000 conform-action transmit exceed-action set-dscp-transmit CS2”

QoS configuration for 19xx/29xx/39xx, 8x9 and 43xx/44xx are almost identical. The key differences are:

The ISR 43xx/44xx series does not currently support the the “police x” bps in the second level

policy. The “shape average” can be used

The ISR 43xx/44xx series does not currently support “bandwidth x” kbps in the second level

policy. The “bandwidth remaining ratio” command is used. Below is a guide on how to use

“bandwidth ratio”