What is the decimal equivalent of the DSCP value AF21?

A.
16

B.
17

C.
18

D.
21

Explanation:
Assured Forwarding (AF) is a means to offer different levels of forwarding
assurances for IP packets. Four AF classes are defined, where each AF class is in each DS node
allocated a certain amount of forwarding resources(buffer space and bandwidth). Within each AF
class IP packets are marked with one of three possible drop precedence values. A congested
node tries to protect packets with a lower drop precedence value from being lost by preferably
discarding packets with a higher drop precedence value. Classes 1 to 4 are referred to as AF
classes. The following table illustrates the DSCP coding for specifying the AF class with the
probability. Bits DS5, DS4 and DS3 define the class; bits DS2 and DS1 specify the drop
probability; bit DS0 is always zero.
he following table illustrates the DSCP coding for specifying the AF class with the probability. Bits
DS5, DS4 and DS3 define the class; bits DS2 and DS1 specify the drop probability; bit DS0 is
always zero.

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