QoS and QoS Policies
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Quality of Service Guide
3HE 11014 AAAC TQZZA Edition: 01
3.2.1.1.1 Hierarchy of Classification Rules
Table 7 shows classification options for various access entities (SAP identifiers) and
service types. For example, traffic from a TDM port using a TDM (Cpipe) PW maps
to one FC (all traffic has the same CoS). Traffic from an Ethernet port using a Epipe
PW can be classified to as many as eight FCs based on DSCP classification rules,
while traffic from a SAP with dot1q or qinq encapsulation can be classified to up to
eight FCs based on dot1p or DSCP rules.
For Ethernet traffic, dot1p-based classification for dot1q or QinQ SAPs takes
precedence over DSCP-based classification. For null-encapsulated Ethernet ports,
only DSCP-based classification applies. In either case, when defining classification
rules, a more specific match rule is always preferred to a general match rule.
For additional information on hierarchy rules, see Table 19 in the Service Ingress
QoS Policies section.
FR (for Fpipes) and HDLC
SAPs
Traffic from an access ingress SAP is mapped to the selected (default) forwarding
class.
DSCP bits When the Ethernet payload is IP, ingress traffic can be mapped to a maximum of
eight forwarding classes based on DSCP bit values.
DSCP-based classification supports untagged, single-tagged, double-tagged, and
triple-tagged Ethernet frames. If an ingress frame has more than three VLAN tags,
then dot1q or qinq dot1p-based classification must be used.
Multi-field classifiers Traffic is classified based on any IP criteria currently supported by the 7705 SAR filter
policies; for example, source and destination IP address, source and destination port,
whether or not the packet is fragmented, ICMP code, and TCP state. For information
on multi-field classification, refer to the 7705 SAR Router Configuration Guide,
“Multi-field Classification (MFC)” and “IP, MAC, and VLAN Filter Entry Commands”.
Table 6 Traffic Classification Types (Continued)
Traffic Classification
Based on...
Description
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