Juniper JUNOSE 11.1.X - QUALITY OF SERVICE CONFIGURATION GUIDE 3-21-2010, Configuration Manual

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Table 18: Operational Shaping Modes for the E120 Router and E320 Router
Operational
Shaping
Mode for
Specific
Port
qos-mode-port
for Port 0 qos-shaping-mode
for Port 0
qos-mode-port
for Specific
Port
qos-shaping-mode
for specific port
Rule
Cell Any Any low-cdv Cell Rule
1
Frame Any Any low-latency or
none Frame
Cell Any Any low-cdv No shaping mode Rule
2
Frame Any Frame low-latency or
none No shaping mode Rule
3
Cell Any Cell low-latency or
none No shaping mode
Cell low-cdv No shaping mode low-latency or
none No shaping mode Rule
4
Frame low-latency or
none No shaping mode low-latency or
none No shaping mode
Related Topics
■
Guidelines for Configuring QoS over ATM on page 166
■
Configuring Default Integrated Mode for ATM Interface on page 168
■
Configuring Low-Latency Mode for Per-Port Queuing on ATM Interfaces on
page 169
■
Configuring Low-CDV Mode for Per-Port Queuing on ATM Interfaces on page 171
■
Configuring the QoS Shaping Mode for ATM Interfaces on page 174
Guidelines for Configuring QoS over ATM
This section provides general QoS configuration guidelines for ATM line modules.
These guidelines are applicable to all JUNOSe releases.
The SAR scheduler generates VC backpressure as a way to control the flow of packets
from the HRR scheduler to the SAR scheduler. The QoS port modes control integration
of the two schedulers.
In default integrated mode, each VC queue in the SAR generates backpressure for
the ATM VC node in the default traffic class group in the HRR. The backpressure
throttles the dequeue rate of the ATM VC node and the nodes and queues stacked
above it in the scheduler hierarchy. VC backpressure is disabled in low-latency QoS
port mode and low-cdv QoS port mode.
166 ■
Guidelines for Configuring QoS over ATM
JUNOSe 11.1.x Quality of Service Configuration Guide