Glossary Of Terms - Comtech EF Data CDM-570A Installation And Operation Manual

QUESTION: What will be the total data rate and what will be the individual data rates?
ANSWER:
•
After serving all high priority queues, only 500 Kbps is left for ASFD classes.
•
This leftover bandwidth is less than the total minimum bandwidth; it must therefore share
the residual 500 Kbps among all four ASFD classes equally - i.e., 500/4=175 Kbps per
class.
•
Since ASFD4 has the service rate 100 Kbps, the excess 75 Kbps will be given the other
queues where the service rate not met.
•
In this case the 75 Kbps again will share equally among ASFD3, ASFD2, and ASFD1
since these service rates were not met.
The resulting individual data rate is as follows:
Stream
Management
Networking Control
Voice
Video
Data-1
Data-2
Data-3
Data-4
Data-5
Data-6
Data-7
TOTAL
L.3

Glossary of Terms

Filtering – QoS allows specific flows to be designated as "filtered," whereby the IP Packet
Processor discards traffic that is otherwise not wanted for forwarding over a satellite link.
Jitter – Measured in milliseconds, this is the amount of variation between two consequent frames
at the receiving end.
Latency – This is the amount of delay, measured in milliseconds, from Ethernet interface of the
near -end modem to the Ethernet interface of the far-end modem.
Maximum Bandwidth – This value can be assigned to a flow to restrict the Maximum Bandwidth
that any particular flow will utilize; otherwise, the default of no bandwidth restriction can be
selected.
Advanced Quality of Service (QoS) Option
CDM-570A/570AL Satellite Modem with Optional Packet Processor
PHB / DSCP
Priority
Code
1 CS7 / b111000
2 CS6 / b110000
3 EXFD / b101110
3 CS5 / b101000
4 CS4 / b100000
5 CS3 / b011000
7 ASFD4 / b100010
7 ASFD3 / b011010
7 ASFD2 / b010010
7 ASFD1 / b001010
8 BE / bXXXXXX
N/A N/A
L–13
Leftover BW (After
Input Data rate
Serving the Queue)
200 Kbps 9.8 Mbps
800 Kbps 9.0 Mbps
1 Mbps 8.0 Mbps
4 Mbps 4.0 Mbps
550 Kbps 3450 Kbps
1450 2000 Kbps
1 Mbps NA
1 Mbps NA
1 Mbps NA
1 Mbps NA
2 Mbps NA
14 Mbps 0 Kbps
Revision 5
QoS output Data rate
200 Kbps
800 Kbps
1Mbps
4 Mbps
550 Kbps
1450 Kbps
100 Kbps
175 + 25 Kbps
175 + 25 Kbps
175 + 25 Kbps
0 Kbps
8.7 Mbps
MN-CDM570A