Traffic Shaping; Queue Bandwidth Limit; Queue Scheduling And Default 802.1P - Zte ZXR10 5900 Series User Manual

The following two methods will be described:
1. Single Rate Three Color Marker (SrTCM)
This algorithm is used in Diffserv traffic conditioner. SrTCM
measures data flow and marks packets according to three traf-
fic parameters (Committed Information Rate, CIR; Committed
Burst Size, CBS; Excess Burst Size, EBS). We call the three
parameters as green, yellow and red marker respectively. A
packet is green if its size is less than CBS. A packet is yellow if
its size is between CBS and EBS and is red if its size exceeds
EBS. By default, red packet is discarded.
2. Two Rate Three Color Marker (TrTCM)
This algorithm is used in Diffserv traffic conditioner. TrTCM
measures IP data flow and marks packets with green, yellow
and red based on two types of rates (Peak Information Rate,
PIR and Committed Information Rate, CIR) and their related
committed burst size (CBS and PBS). A packet is marked in
red if its size exceeds PIR. A packet is marked in yellow is its
size is between PIR and CIR and is marked in green if its size
is less than CIR.

Traffic Shaping

Traffic shaping is used to control the rate of output packets thus
sending packets at even speed. Traffic shaping is used to match
packet rate with downlink equipment to avoid congestion and
packet discarding.
The difference between traffic shaping and traffic policing is that
traffic shaping is to cache packets whose rate exceeds the limited
value and send packets at even rate whereas traffic policing is to
discard packets whose rate exceeds the limited value. Moreover,
traffic shaping makes delay longer but traffic policing does not in-
troduce any extra delay.

Queue Bandwidth Limit

Queue bandwidth limit means limiting the bandwidth of queue on
interface to ensure the minimum bandwidth for queue. When traf-
fic is blocked, certain bandwidth can be ensured for this queue.
Queue Scheduling and Default
802.1p
Each physical port of the ZXR10 5900/5200 supports eight output
queues (queue 0 to queue 7) called
forms incoming port output queue operation according to the CoS
queue corresponding to 802.1p of packets. In network conges-
tion, the queue scheduling is generally used to solve the problem
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Chapter 8 QoS Configuration
CoS queues. The switch per-
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