# DSCP Binary

Please explain to me this type of servcie field binary thing.
You can clearly see that AF11 has been represented as 001010.
My question how can computer avoid 1st right 0.
I knew all those major , minor, and ecn.Please give answers simpley and openly.
My second questions is what is the decimal representation of AF11

https://www.dropbox.com/s/f04zmq63qpgloqv/DSCP.png?dl=0

• Hi,

You are talking about Assured forwarding values.

Please kindly take a look at RFC 2597 too.

the binary number simply represents the translated decimal value of what Assured forwarding class and dropping precedence you are referring to.

DSCP AF21 = 18 = 010010

here you have an Assured forwarding class of 2 and a dropping precedence of 1.

Technically the dropping precedence expresses the dropping probability of the traffic and the class express the priority.

So the higher is the class and less the traffic is subject to drop, the higher is the dropping precedence and more the traffic is subject to drop.

This as i said above because it express a dropping probability. So for example AF41 is less subject to drop than AF43 although it could seem the opposite. Dropping priority values are compared only between same classes. If you have precedences related to different classes than the class is compared first to obtain the higher dropping probability.

To obtain the decimal values you should multiply the class value per 8 and the precedence per 2 and sum the results.

Hope this helps