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Appendix F - Troubleshooting
F.3 Low Throughput Problems
Problem and Indication |
| Possible Cause |
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| Corrective Action |
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Low throughput is suspected |
| Ethernet link problems |
| Verify proper settings of Ethernet | ||
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| operation mode (actual Ethernet speed | |
(Check the dominant Modulation |
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| of 100 Mbps). | |
Level in Per rate Counters and |
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| Check Ethernet counters | |
see expected throughput in the |
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| Wrong configuration of |
| Verify that Maximum Modulation level is not | |||
“Expected Throughput” table |
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| Maximum Modulation |
| set to a value that is not too low according to | |||
below) |
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| level |
| the “Recommended Maximum Modulation | |||
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| Level” table below. | |
Low throughput of |
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| A value that is too low (see the | |||
multicast/broadcast traffic |
| of Multicast Modulation |
| “Recommended Maximum Modulation Level” | ||
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| level |
| table below) may degrade throughput of | ||
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| broadcast and multicast traffic. | |
High retransmissions rate |
| Interference problems |
| Check for interference using the Spectrum | ||
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| (retransmissions rate in |
| Analysis Mode. If necessary, change the | ||
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| excess of 15%) |
| operating frequency of the AU. | ||
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| Expected Throughput in Mbps, TCP Traffic @ 20 MHz Bandwidth, |
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| Burst Mode Enabled, Concatenation Enabled |
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Unit | TCP Traffic |
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| Modulation Level |
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| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 |
Uplink | 1.9 | 1.9 | 1.9 | 1.9 | 1.9 | 1.9 | 1.9 | 1.9 | |
| Downlink | 2.9 | 2.9 | 2.9 | 2.9 | 2.9 | 2.9 | 2.9 | 2.9 |
| Aggregate | 3.3 | 3.3 | 3.3 | 3.3 | 3.3 | 3.3 | 3.3 | 3.3 |
| Uplink | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 | 3.8 |
| Downlink | 4.8 | 5.6 | 5.6 | 5.6 | 5.6 | 5.6 | 5.6 | 5.6 |
| Aggregate | 5 | 6.7 | 7 | 7.1 | 7.1 | 7.2 | 7.2 | 7.2 |
| Uplink | 4.7 | 6.7 | 8.9 | 12.4 | 15.8 | 21 | 25.1 | 26.4 |
| Downlink | 4.8 | 7.1 | 9.4 | 13.7 | 17.7 | 24.7 | 28.9 | 30.1 |
| Aggregate | 4.8 | 7 | 9.3 | 13.1 | 16.9 | 22.8 | 29.4 | 32 |
* The throughput results are for net TCP traffic (excluding protocols overheads)
BreezeACCESS VL System Manual
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