Ericsson ECN330, User Manual

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Configuring the ECN330-switch
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6.14 Class of Service Configuration
Class of Service (CoS) specifies which data packets have greater precedence
when traffic is buffered in the ECN330-switch due to congestion. The ECN330-
switch supports CoS with eight priority queues for each port. Data packets in a
port’s high-priority queue will be transmitted before those in the lower-priority
queues. The default priority for each interface can be set and the mapping of
frame priority tags to the ECN330-switch’s priority queues can be configured.
6.14.1 Layer 2 Queue Settings
6.14.1.1 Setting the Default Priority for Interfaces
The default port priority for each interface on the ECN330-switch can be
specified. All untagged packets entering the ECN330-switch are tagged with the
specified default port priority, and then sorted into the appropriate priority queue
at the output port.
Command Usage
• The ECN330-switch provides eight priority queues for each port. It can
use Weighted Round Robin or Weighted Fair Queuing to prevent head-
of-queue blockage.
• The default priority applies for an untagged frame received on a port set
to accept all frame types (i.e, receives both untagged and tagged
frames). This priority does not apply to IEEE 802.1Q VLAN tagged
frames. If the incoming frame is an IEEE 802.1Q VLAN tagged frame,
the IEEE 802.1p User Priority bits will be used.
• If the output port is an untagged member of the associated VLAN, these
frames are stripped of all VLAN tags prior to transmission.
Command Attributes
• Default Priority – The priority that is assigned to untagged frames
received on the specified port. (Range: 0 - 7, Default: 0)
Note: This parameter is displayed in the CLI as “Priority for untagged traffic."
• Number of Egress Traffic Classes – The number of queue buffers
provided for each port.