## Convert PHB AF to DSCP Decimal and Vise Versa: It’s So Easy!

April 23, 2010 18 Comments

If you are searching any transformation formula from AF to DSCP decimal value and the vise versa then stop here! I have the solution for you! The rules are simple:

**From PHB AF to DSCP Decimal**

Decimal from **AFxy=(8*x)+(2*y)**

So, let’s have some example, let’s calculate decimal value from AF13, AF31 and AF43.

AF13 = (8*1)+(2*3) = DSCP 14

AF31 = (8*3)+(2*1) = DSCP 26

AF43 = (8*4)+(2*3) = DSCP 38

**From DSCP Decimal to PHB AF**

And the formula is tricky to calculate the vise versa, i mean, from DSCP value to PHB AF. The formula is:

*AFxy* where, *x = Floor Value [(DSCP Value)/8], y = [(Remainder)/2]*

So, let’s revert back those DSCP values to AF value.

DSCP 14 = AFxy where, x = Floor Value of (14/8) = 1, y = (Remainder)/2 = 6/2 = 3, so AFxy = AF13

DSCP 26 = AFxy where, x = Floor Value of (26/8) = 3, y = (Remainder)/2 = 2/2 = 1, so AFxy = AF31

DSCP 38 = AFxy where, x = Floor value of (38/8) = 4, y = (Remainder)/2 = 6/2 = 3, so AFxy = AF43

So you will never forget it, right? ðŸ˜€