Cisco CiscoWork QoS Policy Manager 4.1.2 User Guide
Chapter 2 Planning for Quality of Service
What Types of Quality of Service Does QPM Handle?
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User Guide for QoS Policy Manager 3.0
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1 Priority Queue, and 2 Queues 2 Thresholds (1P2Q2T)
1P2Q2T queuing uses three queues:
•
One strict priority queue, usually used for voice traffic
•
One high priority queue with two thresholds
•
One low priority queue with two thresholds
1P2Q2T assigns each precedence to a specific queue and threshold on that queue.
You can mark voice traffic so that it will be assigned to the strict priority queue.
On 1P2Q2T interfaces, the switch services traffic in the strict priority queue
before servicing the standard queues. When the switch is servicing a standard
queue, after transmitting a packet, it checks for traffic in the strict priority queue.
If the switch detects traffic in the strict priority queue, it suspends its service of
the standard queue and completes service of all traffic in the strict priority queue
before returning to the standard queue.
On 1P2Q2T interfaces, the switch services traffic in the strict priority queue
before servicing the standard queues. When the switch is servicing a standard
queue, after transmitting a packet, it checks for traffic in the strict priority queue.
If the switch detects traffic in the strict priority queue, it suspends its service of
the standard queue and completes service of all traffic in the strict priority queue
before returning to the standard queue.
2 Queues, 1 Threshold (2Q1T)
2Q1T queuing uses two queues, with one threshold for each queue. Each pair of
CoS values is associated with either queue 1 or queue 2. For each pair of CoS
values, you can define the queue to which packets with those CoS values will be
directed.
CoS values is associated with either queue 1 or queue 2. For each pair of CoS
values, you can define the queue to which packets with those CoS values will be
directed.
4 Queues, I Threshold (4Q1T)
4Q1T queuing uses four queues, with one threshold for each queue, to determine
the bandwidth allowed for traffic based on each Class of Service (CoS) value.
the bandwidth allowed for traffic based on each Class of Service (CoS) value.
4Q1T queuing comes with a default configuration for the queues, and traffic
assignments based on CoS settings. You can change this configuration if it does
not suit your requirements. You can change the relative WRR weights of the
queues, and the assignment of precedence values to the appropriate queue and
threshold. You do not need to define queuing policies for ports with 4Q1T
queuing.
assignments based on CoS settings. You can change this configuration if it does
not suit your requirements. You can change the relative WRR weights of the
queues, and the assignment of precedence values to the appropriate queue and
threshold. You do not need to define queuing policies for ports with 4Q1T
queuing.