Avaya P550R Manual Do Utilizador

                   5

610-0184-095

June 14, 2001

You can classify traffic by:

■

802.1p tag priority (default)

■

Physical source port 

■

IP characteristics of the frame (source address, destination 
address, and so forth)

Frames are classified into eight priorities, or classes, ranging in 
number from 0 to 7. By default, the switch uses the priority from 
the 802.1p tag field, if present, to assign a priority to a frame.

You can alternately set each physical port with a priority that ranges 
from 0 to 7. The switch then replaces the default 802.1p tag priority 
with the port priority as the priority of the frame. 

You can, as a third alternative, set classification to be performed by 
the IP characteristics of packets, instead of 802.1 tag priority or port 
priority. To classify frames by their IP characteristics, you set a rule 
in an access control list (ACL). The rule can set a priority for traffic 
with a specific IP source address or with a specific combination of IP 
source address, IP destination address, IP protocol, TCP source port, 
and TCP destination port. 

The priority of a rule in an ACL takes precedence over all other 
priorities in Queue Classification and Servicing classification. 
Because of this precedence, the switch determines whether a rule in 
an ACL exists for an IP frame in the final stage of classification. If a 
rule does exist, the priority associated with the rule replaces the 
current priority of the frame. 

The switch then forwards the frames to the appropriate priority 
queue based upon the priority that is assigned to the frames.