Comtech EF Data CDM-570A Installation And Operation Manual page 625

QUESTION: What are the total output data rates and the individual stream data rates?
ANSWER:
•
In Min-Max QoS mode, other than the default rule, which is configured as Priority 9, all
QoS rules are configured as Priority 8.
•
In this mode, the minimum bandwidth for all rules – the excluding the default rule – will be
served first in round robin fashion. In this example, the total minimum BW for Rules 1 and
2 is 5000 Kbps. Since the total bandwidth is 20 Mbps, it has enough bandwidth to serve.
•
After serving the minimum bandwidth, the leftover bandwidth is 15 Mbps (20,000 Kbps–
5000 Kbps).
•
Leftover bandwidth will be served among all rules in round robin fashion until it hits
maximum bandwidth limitations.
•
Each rule's bandwidth is 15/3 = 5000 Kbps.
•
Since Rule 1 maximum clipping was set to 4000 Kbps, and minimum bandwidth has
already taken 2500 bytes, it will use 1500 Kbps more before reaching the maximum
clipping. The leftover 3500 Kbps (5000-1500=3500) is again given to the main pool.
•
Rule 2 does not have enough traffic coming in, so it will use only 2500 kbps (5000-2500);
the remaining bandwidth (5000-2500=2500) is again given to the main pool.
•
Rule 3's input stream is 7000 bytes; it will take its share of the 5000 allocation. Still, it
needs 7000-5000=2000).
•
After serving the fair share, the total leftover bandwidth is 6000 kbps (3500+2500=6000).
•
Since Rule 3 needs the bandwidth, the leftover bandwidth is applied to that rule.
•
After serving Rule 3, the leftover bandwidth 4000 Kbps will be applied to the default
queue.
•
The default rule will see the data rate of4000 Kbps.
The individual rule's data rates are as follows:
QoS Rule
1
2
3
4
Total
Advanced Quality of Service (QoS) Option
CDM-570A/570AL Satellite Modem with Optional Packet Processor
QoS Priority Input Data Rate
1
2
3
9
NA
L–7
QoS Output Data Rate
1000 Kbps
5000 Kbps
7000 Kbps
10000 Kbps
3136 Kbps
Revision 5
4000 Kbps
5000 Kbps
7000 Kbps
4000 Kbps
20000 Kbps
MN-CDM570A