INS_CWGE24MS2_REV–
10/05/16 PAGE 58
INSTALLATION AND OPERATION MANUAL
CWGE24MS2
TECH SUPPORT: 1.888.678.9427
Example:
IP
Header
DSCP=50
=>
45 C8 . . .
Queuing Algorithms
Queuing algorithms allow switches to maintain separate queues for packets from each individual
source or flow and prevent a source from monopolizing the bandwidth.
» Strict-Priority (SPQ)
The packets on the high priority queue are always service firstly.
» Weighted round robin (WRR)
Round Robin scheduling services queues on a rotating basis and is activated only when a port
has more traffic than it can handle. A queue is given an amount of bandwidth irrespective of
the incoming traffic on that port. This queue then moves to the back of the list. The next queue
is given an equal amount of bandwidth, and then moves to the end of the list; and so on,
depending on the number of queues being used. This works in a looping fashion until a queue
is empty.
Weighted Round Robin (WRR) scheduling uses the same algorithm as round robin scheduling,
but services queues based on their priority and queue weight (the number you configure in the
queue Weight field) rather than a fixed amount of bandwidth. WRR is activated only when a port
has more traffic than it can handle. Queues with larger weights get more service than queues
with smaller weights. This queuing mechanism is highly efficient in that it divides any available
bandwidth across the different traffic queues and returns to queues that have not yet emptied.
Default Settings
QoS mode : High First (SPQ)
The mappings of the Priority to Queue are:
PRIO 0 ==> COSQ 2
PRIO 1 ==> COSQ 0
PRIO 2 ==> COSQ 1
PRIO 3 ==> COSQ 3
PRIO 4 ==> COSQ 4
PRIO 5 ==> COSQ 5
PRIO 6 ==> COSQ 6
PRIO 7 ==> COSQ 7
The DiffServ is disabled on the switch.
