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Parameters
diffserv Enter the keyword diffserv to specify trust of DSCP markings.
dot1p Enter the keyword dot1p to specify trust dot1p configuration.
fallback Enter the keyword fallback to classify packets according to their DSCP value as
a secondary option in case no match occurs against the configured class maps.
Defaults none
Command Modes CONFIGURATION (conf-policy-map-in)
Supported Modes Programmable-Mux (PMUX)
Full–Switch
Command
History
Version Description
9.9(0.0) Introduced on the FN IOM.
9.4(0.0) Supported on the FN I/O Aggregator.
Usage
Information
When you configure trust, matched bytes/packets counters are not incremented in the show qos
statistics command.
Dynamic mapping honors packets marked according to the standard definitions of DSCP. The following
lists the default mapping.
Table 3. Default Mapping
DSCP/CP hex
Range (XXX)
DSCP Definition Traditional IP
Precedence
MXL Switch
Internal Queue
ID
DSCP/CP
Decimal
111XXX Network Control 3 48–63
110XXX Internetwork
Control
3 48–63
101XXX EF (Expedited
Forwarding)
CRITIC/ECP 2 32–47
100XXX AF4 (Assured
Forwarding)
Flash Override 2 32–47
011XXX AF3 Flash 1 16–31
010XXX AF2 Immediate 1 16–31
001XXX AF1 Priority 0 0–15
000XXX BE (Best Effort) Best Effort 0 0–15
Quality of Service (QoS) 973