Filters and QoS Configuration for ERS 5500
Technical Configuration Guide
v2.0
NN48500-559
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polices. The ‘well-know’ DSCP values can be viewed by using the NNCLI command
‘show qos eqressmap’.
•
Untrusted Ports
o
Assumes that all traffic coming into the port is suspect. Therefore, the DSCP field of
any traffic that enters the Ethernet Routing Switch 5500 from an Untrusted Port is re-
marked. For untagged packets, the default classifier is used to change the DSCP.
This results in a DSCP value determined by the CoS-to-DSCP mapping table using
the default 802.1p priority of the interface where the packet is received. For tagged
packets, the 802.1p value is determined by CoS-to-DSCP mapping table using the
best effort DSCP, which is 0.
•
Unrestricted Ports
o
Does not assume anything about the origin of the incoming traffic. You may assign
an action to set the DSCP or not to set the DSCP; it's up to you. This allows you to
manipulate the DSCP value based upon the filter criteria, and not upon the point of
origin.
The following table displays a summary of the role combination capabilities.
Table 1: Default QoS Action
Type of Filter
Action
Trusted
Untrusted
Unrestricted
DSCP
Does not
change
•
Tagged--Updates to 0
(Standard)
•
Untagged--Updates using
mapping table and port’s
default value
Does not
change
IPv4 filter criteria
or Layer 2 filter
criteria matching
IPv4
IEEE
802.1p
Updates
based on
DSCP
mapping
table value
Updates based on DSCP
mapping table value
Does not
change
Classification
Classification identifies the traffic flow that requires QoS management. The traffic flow may be
identified by the Layer 2 or IP content of the frame using any of the elements shown below.
Layer 2 Classifier Elements
o
Source MAC with mask to filter on complete or partial MAC addresses
o
Destination MAC with mask to filter on complete or partial MAC addresses
o
VLAN ID – can be a range
o
Tagged or untagged packets
o
EtherType
o
802.1p
priority
•
IP Classifier Elements
o
Source IPv4/v6 host or subnet