Classifying Bridged Traffic As Layer 3 - Alcatel-Lucent OmniSwitch 9900 Series Network Configuration Manual

Configuring QoS
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If a packet ingresses on a trusted port and does not match any QoS policy that sets priority, then the
existing 802.1p value (non-IP packets) or the ToS/DSCP value (IP packets) or the default classification
priority configured for the port is used to determine priority for the packet.
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If a packet ingresses on an untrusted port and does not match any QoS policy that sets priority, then the
default 802.1p value configured for the port (tagged/untagged non-IP packets) or the default ToS/
DSCP value configured for the port (IP packets) is used to determine priority for the packet.
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If the default classification value for the port is set to DSCP, the DSCP value of a tagged IP packet is
mapped to the 802.1p value for that same packet. In other words, the 802.1p priority is overwritten
with the precedence bits of the DSCP value. This does not apply to Layer 2 packets. See
the 802.1p Priority for IP Packets" on page 26-64
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The egress priority for a packet ingressing on a VLAN Stacking port (a trusted port) is set using the
existing 802.1p value or configured through an associated VLAN Stacking service.
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IP phone traffic is automatically trusted by default. See
Traffic" on page 26-6

Classifying Bridged Traffic as Layer 3

In some network configurations it is required to force the switch to classify bridged traffic as routed
(Layer 3) traffic. Typically this option is used for QoS filtering. See
page 26-63 for more information about filtering.
The Layer 3 classification of bridged traffic is no different from the classification of normal Layer 3
routed traffic. Note that this implementation of QoS always performs Layer 3 classification of bridged
traffic; it is not an option. As a result,
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Layer 3 ACLs are always effected on bridged traffic.
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The switch can bridge and route traffic to the same destination.
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All IP packets are prioritized based on ToS if the default classification on the port is set to DSCP. If
DSCP is not the default classification, then the IP packets are prioritized based on 802.1p.
Note that Layer 3 ACLs are effected on bridged IP traffic and Layer 2 ACLs are effected on routed traffic.
Automatic QoS Prioritization for IP Phone Traffic
Automatic QoS prioritization refers to prioritizing certain subsets of switch traffic without having to
configure a specific QoS policy to do the same for each type of traffic. This functionality is currently
available for IP phone traffic.
The switch automatically trusts the priority of IP phone traffic by default. This means that the priority
value contained in packets originating from IP phones is used for the ingress priority. The default priority
value configured for the QoS port receiving such traffic is used for the egress priority of the packet.
IP phone traffic is detected by examining the source MAC address of the packet to determine if the
address falls within the following ranges of IP phone MAC addresses:
00:80:9f:00:00:00 – 00:80:9f:ff:ff:ff
00:13:fa:00:00:00 – 00:13:fa:ff:ff:ff
In addition to prioritizing IP phone traffic, it is also possible to automatically prioritize non-IP phone
traffic. This is done by adding up to four MAC addresses or four ranges of MAC addresses to the
predefined QoS "alaPhone" MAC address group. See
information.
OmniSwitch AOS Release 8 Network Configuration Guide
for more information.
for more information.
"Automatic QoS Prioritization for IP Phone
"Using Access Control Lists" on
"Creating MAC Groups" on page 26-57
December 2017
Classification
"Maintaining
for more
page 26-6