Specifying Layer 2 Marking - Patton electronics SmartWare R.3.20 Software Configuration Manual

SmartWare Software Configuration Guide
"traffic-class" number called. With SmartWare you can inspect the DSCP value in the ACL rules and modify
the DSCP value with the link scheduler
Note
When configuring service differentiation on the SmartNode, ensure that
codepoint settings are arranged with the service provider.
The command set ip dscp
needed to make the class conformant. The
Mode: Source
Command
node (src)[ name ]#set ip dscp value

Specifying layer 2 marking

The IEEE ratified the 802.1p standard for traffic prioritization in response to the realization that different traf-
fic classes have different priority needs. This standard defines how network frames are tagged with user priority
levels ranging from 7 (highest priority) to 0 (lowest priority). 802.1p-compliant network infrastructure devices,
such as switches and routers, prioritize traffic delivery according to the user priority tag, giving higher priority
frames precedence over lower priority or non-tagged frames. This means that time-critical data can receive pref-
erential treatment over non-time-critical data.
Under 802.1p, a 4-byte Tag Control Info (TCI) field is inserted in the Layer 2 header between the Source
Address and the MAC Client Type/Length field of an Ethernet Frame.
Tag Control Field
Tagged Frame Type Interpretation
3-Bit Priority Field (802.1p)
Canonical
12-Bit 802.1Q VLAN Identifier
802.1p-compliant infrastructure devices read the 3-bit user priority field and route the frame through an inter-
nal buffer/queue mapped to the corresponding user priority level.
The command set layer2 cos
priority field (802.1p). The
Please note that the Ethernet port must be configured for 802.1Q framing. Standard framing has no class-of-
service field.
Mode: Source
Command
node (src)[ name ]#set layer2 cos value Defines the Class-Of-Service value applied to packets of for the
Link scheduler configuration task list
set ip dscp
sets the DS field applied to packets of the class name. Additionally shaping may be
form of this command disables packet marking.
no
Defines the Differentiated Services Codepoint value applied to
packets of for the selected class or policy name . The range for
value is from 0 to 63.
Table 6. Traffic control info (TCI) field
Always set to 8100h for Ethernet frames (802.3ac tag format)
Value from 0 to 7 representing user priority levels (7 is the highest)
Always set to 0
VLAN identification number
specifies the layer 2 marking applied to packets of this class by setting the 3-bit
form of this command disables packet marking.
no
selected class or policy name . The range for value is from 0 to 7.
13 • Link scheduler configuration
command.
Purpose
Table 6
Description
Purpose
lists the tag components.
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