atmIfCANrtVbrTxQueueLimit 1.3.6.1.4.1.562.2.4.1.114.3.4.100.1.4

This attribute specifies the default maximum queue length for the emission queues used to buffer the traffic of the nrt-VBR service category. It is used as the basis for setting the discard thresholds on both common and per-VC queues. For the common queue, the discard thresholds are set at approximately 35, 75, and 90 percent of the value of this attribute for traffic at discard priority 3 (DP=3), DP=2, and DP=1 respectively. For per-VC queue, the actual limit may be reduced depending on the shaping rate of the connection (for standard Vpt Vccs, this is the shaping rate of the Vpt). The discard thresholds are set at approximately 35, 75, and 90 percent of the scaled queue limit for traffic at discard priority 3 (DP=3), DP=2, and DP=1 respectively. However, a reduction will never result in a value that is less than the value set for the minPerVcQueueLimit attribute. When the value of this attribute is autoConfigure, an appropriate value is selected based on the card type. It is set to 1792 for low speed cards such as DS1, E1, and IMA, set to 2304 for high speed CQC-based ATM cards such as JT2, DS3, E3 and OC3, and set to 10240 for high speed ATM IP cards such as 3pDS3Atm2, 3pE3Atm2, 2pOC3SmAtm2 and 2pOC3MmAtm2. For ATM IP FPs, the per-VC queue limit may be overridden for a permanent connection by specifying a value in the Vcd Tm or Vpd Tm txQueueLimit attribute. On CQC-based ATM cards, this attribute must be set to the same value for CA NrtVbr, Abr and Ubr components. The operational value of the maximum length of a queue (common or per-VC) is indicated by the Vcc Tm, Vpc Tm, or Vpt Tm txQueueThresholds attribute. When using per-VC queueing, this attribute is used as the default txQueueLimit for all standard Vpts, regardless of their atmServiceCategory. This attribute does not apply to basic Vpts. VALUES ( 0 = autoConfigure )