Alcatel-Lucent 7750 SR OS, Руководство по настройке интерфейса

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Interface Configuration
7750 SR OS Interface Configuration Guide Page 41
Note that all queue threshold and queue scheduling parameters are adjusted to the available bundle
rate. If a member link goes down or a new member link is added to the bundle, the scheduling
parameters MIR, W1, W2, W3, as well as the per class queue thresholds OOP and max are
automatically adjusted to maintain the same values.
Class 0 queue is serviced at MLPPP at available bundle rate. Class 1 queue is guaranteed a
minimum service rate but is allowed to share additional bandwidth with class 2 and 3 queues
based on the configuration of WRR weight W1.
Class queues 2 and 3 can be given bandwidth guarantee by limiting MIR of class 1 queue to less
than 100% and by setting the WRR weights W1, W2, and W3 to achieve the desired bandwidth
distribution among all three class queues.
Note that there is one queue per bundle member link to carry link control packets, such as LCP:
PPP, and which are serviced with strict priority over the 4 class queues (not shown).
In the default 2-class, 3-class, and 4-class egress QoS profile, the class queues are service with
strict priority in ascending order of class number.
Ingress MLPPP Class Reassembly
For a MLPPP bundle with the multi-class option enabled, there is a default profile for setting the
re-assembly timer value for each class. When the pre-defined MLPPP ingress QoS profile 1 is
applied to a 4-class bundle, the values of the timers are modified as shown in
Table 9 .
Table 9: MLPPP Ingress QoS Profile: Reassembly Timers (msec)
Class 0 Class 1 Class 2 Class 4
MLPPP ingress QoS default profile
(2-Class bundle) 25ms 25ms NA NA
MLPPP ingress QoS default profile
(3-Class bundle) 25ms 25ms 25ms NA
MLPPP ingress QoS default profile
(4-Class bundle) 25ms 25ms 100ms 1000ms
MLPPP ingress QoS profile 1 (4-class bundle) 10 10 100 1000