Juniper JUNOS 10.1 - CONFIGURATION GUIDE 1-2010 Configuration Manual page 419

Configuring an ATM Scheduler Map
To define a scheduler map, you associate it with a forwarding class. Each class is
associated with a specific queue, as follows:
NOTE: For M320, M120, and T Series routers only, you can configure more than four
forwarding classes and queues. For more information, see "Enabling Eight Queues
on ATM2 IQ Interfaces" on page 350.
When you configure an ATM scheduler map, the JUNOS Software creates these CoS
queues for a VC. The JUNOS Software prefixes each packet delivered to the VC with
the next-hop rewrite data associated with each queue.
To configure an ATM scheduler map, include the
[edit interfaces at-fpc/pic/port atm-options]
You can define the following options for each forwarding class:
A linear RED profile defines the number of cells using the
within the RED profile. (You configure the
at-fpc/pic/port atm-options linear-red-profiles profile-name]
—Define CoS VC drop profile fill-level percentage when linear
high-plp-threshold
RED is applied to cells with high PLP. When the fill level exceeds the defined
percentage, packets with high PLP are randomly dropped by RED.
low-plp-threshold —Define CoS VC drop profile fill-level percentage when linear
RED is applied to cells with low PLP. When the fill level exceeds the defined
percentage, packets with low PLP are randomly dropped by RED.
—Queue 0
best-effort
—Queue 1
expedited-forwarding
assured-forwarding —Queue 2
—Queue 3
network-control
edit interfaces at-fpc/pic/port atm-options]
scheduler-maps map-name {
forwarding-class class-name {
epd-threshold cells plp1 cells;
linear-red-profile profile-name;
priority (high | low);
transmit-weight (cells number | percent number);
}
}
or
epd-threshold linear-red-profile
that can be stored with tail drop. When a BOP cell is received, the VC s queue
depth is checked against the EPD threshold. If the VC s queue depth exceeds the
EPD threshold, the BOP cell and all subsequent cells in the packet are discarded.
Chapter 13: Configuring ATM Interfaces
scheduler-maps
hierarchy level:
—An EPD threshold provides a queue of cells
statement at the
queue-depth
hierarchy level.)
Configuring ATM2 IQ VC Tunnel CoS Components
statement at the
queue-depth statement
[edit interfaces
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