Firewall > QoS Mapping
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SonicOS Enhanced 4.0 Administrator Guide
Example of Outbound BWM
The above diagram shows 4 policies are configured for OBWM with a link capacity of 100 Kbps.
This means that the link capacity is 12800 Bytes/sec. Below table gives the BWM values for
each rule in Bytes per second.
a. For GBW processing, we start with the first queue in the rule queue list which is FTP.
Link credit is 12800 and class credit is 1280. Pkt1 of 400B is sent out on the WAN link
and link credit becomes 12400 and class credit becomes 880. Pkt2 is not sent out
because there is not enough class credit to send 1500 Bytes. The remaining class
credit is carried over to the next time slice.
b. We move on to the next rule queue in this list which is for H323. Pkt1 of 1500B is sent
out and link credit becomes 10900 and class credit for H323 becomes 1060. Pkt2 is
also sent from queue hence link credit = 10200 and class credit = 360. Pkt3 is not sent
since there is not enough class credit. The remaining class credit is carried over to the
next time slice.
c. Now we move onto Yahoo Messenger queue. Since Pkt1 cannot be accommodated
with its class credit of 640 Bytes, no packets are processed from this queue. However,
its class credit is carried over to the next time slice.
d. From VNC queue, Pkt1 and Pkt2 are sent out leaving link credit = 8000 and class credit
= 360. Class credit is carried over.
e. Since all the queues have been processed for GBW we now move onto use up the left
over link credit of 8000.
BWM values FTP H323 Yahoo Messenger VNC
GBW 1280 2560 640 2560
MBW 2560 5120 1920 3200