Hitachi GR2000 Series manual Relationship between number of queues and priority

Filtering/QoS Information

Specifies the queuing priority after having been changed. If this parameter is specified and the output line is ATM, it is possible to set the cell loss priority indication bit (CLP bit) of a cell transmitted by VC to zero when the queuing priority is three or four, and to one when the queuing priority is one or two. For setting the cell loss indication bit, please refer to in GR2000 Configuration Commands, (universal CLI) Vol. 1.

-penalty_Specifiesdscp<DSCPthe _DSCPValue>rewriting: value and controls QoS by using the rewritten DSCP.

However, what is rewritten is the six high-order bits in the DSCP field.

The two low-order bits are ignored even if they are set.

27	26	25	24	23	22	21	20
		DSCP				CU
	High-order 6 bits are designated.
DSCP(Differentiated Services Code Point), CU(Current Unused)
Default:	When setting -upc: -penalty_drop
	When setting -max_rate: -penalty_drop (Packets breaching the
	maximum band are all discarded.)
	When setting -min_rate: -discard 1 (Packets breaching the
	minimum band are discarded more easily.)
Range of value:	-penalty_dscp <DSCP_Value>: 0 to 63 (decimals)
	-penalty_discard <No>: 1-4
	(The smaller the value of the queuing priority, the more
	preferentially the packet is discarded.)
Table 1-53 Relationship between number of queues and priority
Setting Condition				Range
Interface Using	No. of Queue in			Queuing Priority
this List	Output Interface
Input side	--			1-4
Output side	4			1-4
Output side	8			1-4
Output side	16			1-4
Output side	32			1-4
Output side	64			1-4
Output side	250			1-4 (*2)
Output side	1000			1-4 (*2)
*1: If value outside the	range is set in output			priority, the setting contents are nullified.
*2: If the QoS attribute of the output interface is the minimum band assurance (specified by kbps), the
flow control is executed as follows:
• Queuing priority 1 and 2: Flow control is executed at queuing priority 2.
• Queuing priority 3 and 4: Flow control is executed at queuing priority 4.

Note: Depending on setting of the important packet protection function, maximum band

*restriction and minimum band guarantee, the number of entry used per list will be the number of entry used per list for each setting as shown in Table 1-54.

GR2K-GA-0014	1-97
Ver. 07-02