642-642 QOS VIDEO TRAINING: Traffic Policing

642-642 QOS VIDEO TRAINING: Traffic Policing

Policing + Shaping – Dropping traffic down to a level so it wont consume bandwidth for business applications.

PolicingDrop or Mark(Remark) Exceeding/Excess traffic. Bandwidth upper limit is specified.

ShapingQueues excess traffic and sends at a desired rate. Only really an interim feature.. not really a fix.. Same concept as a ‘map-class’. Implemented using Class Maps.

Policing Implementation

1. Class Map – Match-ANY GARBAGE

match protocol edonkey/kazaa/nutella etc… (Using NBAR)

2. Policy Map – GARBAGE_SMACKDOWN

class GARBAGE

police

conform-action – ‘single bucket policing’

transmit

exceed-action

drop

IMAGE TO GO HERE

Has to be applied to the interface. Policing is done on the INBOUND direction, which is rare within QoS.

int fa0

service-policy input GARBAGE_SMACKDOWN

show policy-map interface Fa0

The Token Buckets

How much data the router can hold onto at any time…

Single Bucket Model

Conform Rate

Dual Token Buckets – Gives traffic a second chance..

1 Bucket for Conform (Bc)

1 Bucket for Exceed (Be)

As soon as exceed-action is set you are telling the router to use a Dual Token Bucket model.

Bucket number 3 = violate-action – drop

show policy-map

Policy Map GARBAGE_SMACKDOWN

Exceed burst also created, if you dont specify burst amounts, Cisco router will do for you. Takes CIR and divides by 32 for the Be value.

IMAGE TO GO HERE

Advertisements