User's Manual

Technical Notes – QoS Features on BES50

BES50 Re-Marking Capability

In addition to traffic prioritization, BES50 also provides the capability to re-mark the IP DSCP value of an

outgoing IP packet and the 802.1p value (CoS) of an outgoing Ethernet frame.

IP DSCP Re-Marking on BES50FE

Figure 6: BES50FE Traffic Prioritization Flow Chart depicts the flow chart of how CoS/priority is determined by

BES50FE. Re-marking in BES50FE is a simple extension to this process. BES50FE always re-marks the 802.1p

value of the tagged egress Ethernet frame with the determined CoS/priority value. On the other hand, BES50FE

will only re-mark IP DSCP of the outgoing IP packet if the matched QoS Policy has an associated “Set IP

DSCP” action (see Figure 14: BES50FE Policy Setting DSCP Value).

IP DSCP Re-Marking on BES50GE

Figure 7: BES50GE Traffic Prioritization Flow Chart depicts the flow chart of how the priority index and

CoS/priority are determined by BES50GE. Just like BES50FE, BES50GE always re-marks the 802.1p value of

the tagged egress Ethernet frame with the determined CoS/priority value. Re-marking IP DSCP in BES50GE is

slightly different from BES50FE.

By default, IP DSCP re-marking is disabled on all the ports. The user must manually enable IP DSCP re-

marking on the egress port (i.e. the port in which IP packet is emitted out from BES50GE) if they desired to do

so. To enable/disable IP DSCP re-marking on an egress port, navigate to the Applications > Priority > Marker

Status panel.

Figure 18: BES50GE IP DSCP Re-Marking Status