Convert PHB AF to DSCP Decimal and Vise Versa: It’s So Easy!
April 23, 2010 19 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? 😀