Using Differentiated Services Codepoint (DSCP) mapping
The DSCP Policy Table associates an 802.1p priority with a DSCP codepoint in an IPv4/IPv6 packet. Using DSCP codepoints in your network allows you to set a LAN policy that operates independently of 802.1Q VLAN-tagging.
In the default state, most of the 64 codepoints do not assign an 802.1p priority, as indicated by
No-override
in the following Default DSCP policy table. However, some codepoints, such as Assured Forwarding and Expedited Forwarding, have a default 802.1p priority setting.
Use the following commands to display the DSCP Policy table, configure the codepoint-priority assignments, and assign optional names to the codepoints.
Syntax:
show qos dscp-map
Displays the DSCP Policy table.
qos dscp-map codepoint priority0 - 7 [name ascii-string]
Configures an 802.1p priority for the specified codepoint and an optional (DSCP policy) name.
no qos dscp-map codepoint
Removes the currently configured 802.1p priority that is associated with the specified
codepoint and displays the
No-override
setting. The codepoint policy name, if configured, is also removed.
no qos dscp-map codepointname
Deletes only the policy name, if configured, for the specified
codepoint
.
DSCP Policy |
802.1p Priority |
DSCP Policy |
802.1p Priority |
DSCP Policy |
802.1p Priority |
---|---|---|---|---|---|
000000 |
No-override |
010110 |
31 |
101011 |
No-override |
000001 |
No-override | 0 10111 | No-override | 101100 | No-override |
000010 |
No-override | 011000 | No-override | 101101 | No-override |
000011 |
No-override | 011001 | No-override | 101110 | 71No-override |
000100 |
No-override | 011010 | 41 | 101111 | No-override |
000101 |
No-override | 011011 | No-override | 110000 | No-override |
000110 |
No-override | 011100 | 41 | 110001 | No-override |
000111 | No-override | 011101 | No-override | 110010 | No-override |
001000 | No-override | 011110 | 51 | 110011 | No-override |
001001 | No-override | 011111 | No-override | 110100 | No-override |
001010 | No-override | 100000 | No-override | 110101 | No-override |
001011 | 11 |
100001 | No-override | 110110 | No-override |
001100 | No-override | 100010 | 61 | 110111 | No-override |
001101 | 21 | 100011 | No-override | 111000 | No-override |
001110 | No-override | 100100 | 61 | 111001 | No-override |
001111 | No-override | 100101 | No-override | 111010 | No-override |
010000 | No-override | 100110 | 71 | 111011 | No-override |
010001 | 01 | 100111 | No-override | 111100 | No-override |
010010 | No-override | 101000 | No-override | 111101 | No-override |
010011 | 01 | 101001 | No-override | 111110 | No-override |
010100 | No-override | 101010 | No-override | 111111 | |
010101 |
Expedited Forwarding codepoint configured by default.