mscAtmIfCANrtVbrTxQueueLimit
1.3.6.1.4.1.562.36.2.1.114.3.4.100.1.4
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 the 1pOC12SmLrAtm card, if autoConfigure is selected for
this attribute then the value is set to 7680.
For the 1pOC48SmSrAtm card, if autoConfigure is selected for this
attribute the the value is set to 122880.
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.
For the 1pOC48SmSrAtm card, the value of this attribute is used to
set the maximum size of the link-class queue for buffering the nrt-
VBR traffic on the egress path.
On CQC-based ATM cards, this attribute must be set to the same
value for CA NrtVbr, Abr and Ubr components, and the valid range
is from 5 to 30000 inclusive.
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.
VALUES (
0 = autoConfigure
)