Comtech EF Data CDM-425, Инструкция по установке и эксплуатации

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CDM-425 Advanced Satellite Modem
Revision 0
Appendix M M–11 MN-CDM-425
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 of 4000 Kbps.
•
The individual rule’s data rates are as follows:
QoS Rule Layer 3 QoS Priority Input Data Rate QoS Output Data Rate
1 1 10000 Kbps 4000 Kbps
2 2 5000 Kbps 5000 Kbps
3 3 7000 Kbps 7000 Kbps
4 9 10000 Kbps 4000 Kbps
Total ► 32000 Kbps 20000 Kbps