Allied Telesis AT-S63 - Manual (Page 343)

AT-S63 Management Software Menus Interface User’s Guide
Section II: Advanced Operations 343
Configuring CoS
As explained in “Class of Service Overview” on page 338, a tagged packet
received on a port is placed it into one of four priority queues on the egress
port according to the switch’s mapping of 802.1p priority levels to egress
priority queues. The default mappings are shown in Table 6 on page 339.
However, you can override the mappings at the port level so that all
tagged packets are placed into a specific egress priority queue regardless
of the priority level in the packets themselves. Note that this determination
is made when a packet is received on the ingress port and before the
frame is forwarded to the egress port. Consequently, you need to
configure this feature on the ingress port.
For example, when you configure a switch port so that all ingress tagged
frames are handled by the egress priority queue Q2, all tagged frames
received on the port are directed to the Q2 priority egress queue on the
egress ports.
You can also use CoS to control which priority queue handles untagged
frames that ingress a port. By default, untagged frames (that is, frames
without VLAN or priority level information) are automatically assigned to
Q0, the lowest priority queue. But you can configure CoS on a port so that
all untagged frames received on the port are directed to one of the other
queues.
To configure CoS for a port, perform the following procedure:
1. From the Main Menu, type 7 to select Security and Services.
The Security and Services menu is shown in Figure 82 on page 259.
Note
Items 7, 8, and 9 are not available in all versions of the AT-S63
management software. Contact your sales representative to
determine if these features are available for your locale.
2. From the Security and Services menu, type 5 to select Class of
Service (CoS).