Classification And Replacement Policies - Extreme Networks PoS Installation And User Manual

Configuring the PoS Module

Classification and Replacement Policies

This section deals primarily with classification operations performed by IPCP or BCP
configured PoS ports.
Most of the existing ingress classification functions are supported for IPCP or BCP
configured PoS ports. Functions such as access list and destination MAC address QoS
policies are supported, as is the command.
enable diffserv replacement
Egress frames are always assigned to a QoS profile based on their 802.1p priority. Thus,
when a PoS port receives a frame from the switch fabric with a priority value n, that
frame is assigned to egress QoS profile qpn+1.
The existing and
enable diffserv examination ports disable diffserv
commands are used on PoS ports to control whether the DiffServ
examination ports
code point (DSCP) is examined for ingress classification purposes.
When you enable the PPP Bridging Control Protocol (BCP) on a PoS port, non-IP frames
that contain a VLAN tag are assigned to an ingress QoS profile based on their 802.1p
priority value. You can configure this assignment using the
config dot1p type
command, which is used to specify the mappings between 802.1p priority values and
QoS profiles. However, if a PoS port receives a frame with a priority value n, for which
there is no mapping to one of the eight profiles (qp1-qp8), that frame is assigned to
ingress QoS profile qpn+1.
If is not enabled, then the preceding 802.1p priority
diffserv examination
classification rules are applied to tagged IP frames as well.
In both cases, untagged frames are assigned to a single ingress QoS profile (provided
that the port is an untagged member of a VLAN; if that is not the case, then untagged
frames are discarded). This QoS profile defaults to qp1, but you can assign it to another
profile using the command or
config ports <portlist> qosprofile <qosprofile>
the command (where the port-based
config vlan <name> qosprofile <qosprofile>
QoS configuration has higher precedence than VLAN-based QoS).
Additionally, if you enable the PPP IP Control Protocol (IPCP) on a PoS port and do not
enable on the port, then all ingress frames (received from the
diffserv examination
SONET link) are assigned to a single ingress QoS profile. The profile defaults to qp1,
but you can configure it to another profile using the
config ports <portlist>
command or the
qosprofile <qosprofile> config vlan <name> qosprofile
command.
<qosprofile>
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