The correspondence between DSCP, priority, and class

The DSCP priority (0-lowest) is inverse to the priority of classes in HTB policing (0-highest). Therefore if you need to mark packages for external platforms, you need to set class_order=1 and use the following table to get the correspondence between DSCP values and traffic classes in HTB. If you do not need to mark packages, then it is more convenient to use intuitive correspondence: dscp cs0↔htb class0 (at setting class_order=0 by default).

DSCP Name	Binary Value	Decimal Value	Priority	Policing Class	Policing class at setting class_order=1
CS0	000 000	0	0	0	7
CS1	001 000	8	1	1	6
AF11	001 010	10	1	1	6
AF12	001 100	12	1	1	6
AF13	001 110	14	1	1	6
CS2	010 000	16	2	2	5
AF21	010 010	18	2	2	5
AF22	010 100	20	2	2	5
AF23	010 110	22	2	2	5
CS3	011 000	24	3	3	4
AF31	011 010	26	3	3	4
AF32	011 100	28	3	3	4
AF33	011 110	30	3	3	4
CS4	100 000	32	4	4	3
AF41	100 010	34	4	4	3
AF42	100 100	36	4	4	3
AF43	100 110	38	4	4	3
CS5	101 000	40	5	5	2
EF	101 110	46	5	5	2
CS6	110 000	48	6	6	1
CS7	111 000	56	7	7	0

Priority is a subset of the DSCP field in the IP header. In cases of VLAn/QinQ and MPLS it is a separate field in a range of values 0..7. The settings indicate the full DSCP value, which is used in case of marking up IP traffic, and in other cases only priority is used.