QoS Traffic Policing Explained

Hi Muhammad,

Policing is typically implemented by ISPs to limit the traffic of their customers so it will depend on the traffic contract that they sell you.

The single rate two color policer might be a bit unfair since it doesn’t allow bursting. With a CIR of 128kbps then you’ll only be able to reach 128kbps if you keep sending traffic non-stop.

The single rate three color policer allows bursting. Since data traffic is “bursty” by nature, this is probably a bit more fair to use. When your connection is idle, you can accumulate up to the Be and spend your Bc+Be when required.

The Dual rate three-color policer is useful when the ISP is selling more bandwidth than they actually can offer. It’s very unlikely that all customers are sending at maximum capacity all the time so they can offer you a “dual rate” contract. You might pay for a CIR of 128kbps and go up to 256kbps when the network is underutilized.

Rene