Efci, Epd, And Rm Cell Marking - Cabletron Systems SmartSwitch 6500 User Manual

Traffic Management
7.1.4

EFCI, EPD, and RM Cell Marking

To control switch congestion, the SmartSwitch 6500 implements standard resource management cell (RM-cell)
marking, explicit forward congestion indicator cell marking (with backward RM cell marking), and early packet
discard (EPD). These congestion control schemes are triggered when the number of cells within shared memory
reaches user-definable thresholds. Use the
For example, enter the
show switchtrafficcongestion
Smart6500 # show switchtrafficcongestion
Switch Traffic Congestion Parameters
==============================================================================
Low EPD Threshold
High EPD Threshold
CLP1 Discard Threshold
RM Cell Marking Enable
EFCI Cell Marking Enable
Explicit Rate Marking Enable
Smart6500 #
For most types of traffic, EPD triggering is tied to the low EPD threshold. Signaling traffic, however, is tied to the high
EPD threshold; this assures that signaling packets are discarded only when congestion is most severe.
Use the
set switchtrafficcongestion
EFCI cell marking. For example:
Smart6500 # set switchtrafficcongestion
LowEPDWatermark(4096)
HighEPDWatermark(4096)
CLP1_DiscardWatermark(4096)
RMCellMarkingEnable(enable)
ExplicitRateMarkingEnable(enable)
EFCIMarkingEnable(enable)
Smart6500 #
switchtrafficcongestion
command.
: 209715 cells
: 104857 cells
: 131072 cells
: OFF
: OFF
: OFF
command to change thresholds for EPD and to enable or disable RM and
:
:
:
:
:
:
Traffic Management Capabilities
commands to view and set these thresholds.
SmartSwitch 6500 User Guide 7-7