PVA-3000 Reference Manual
December 2, 2019 Sifos Technologies
Minimizing effects of impairments to TEST PHY (see Asymmetric Features in Section 2.2.7)
Measuring effects of impairments on TEST PHY (100BaseTx and 1000BaseT)
Priming switch bridges to assure packet flows (Packet Flow metering only)
Receiver testing, even with the benefit of controlled impairments, can take many minutes to complete. Each of the
receiver tests attempts to minimize execution time by applying more severe impairments of each impairment class, then
if the result is successful, lesser impairment conditions for each impairment class are assumed successful. For example,
if a measurement with Line Loss and +12dB Noise impairment is 100% successful, the test condition of Line Loss and
+6 dB Noise impairment is avoided.
Receiver tests configured (from PowerShell PSA) using the Link Monitor measurement and excluding the Line Loss
impairment can be meaningful when testing remote Ethernet service outlets for service quality.
5.4.1. 10BaseT Receiver Test
The 10BaseT receiver test, pva_rx_10, will evaluate each connection polarity supported by the DUT. If the DUT is
MDI only, then only the receiver connected to pair 3 is tested and if it is MDI-X only, pair 2 is tested. If the port is
auto-MDI, then all testing is performed on both pair 2 and pair 3 (MDI-X and MDI modes).
The impairments utilized for each connection polarity during the 10BaseT receiver test are:
Line Loss* + Low Transmit Level + Low Slew Rate
Line Loss* + Transmit Frequency Offset (+50 and +100ppm)
Line Loss* + Random Noise (+10 and +14 dB) where 0 dB Noise = 40mV
pk-pk
Line Loss* + Random Jitter (e.g. +13.5** and +18** dB) where 0 dB Jitter = 1.4nsec
pk-pk
Line Loss* + Random Noise (e.g. +10.5 and +13.5 dB) + Random Jitter (e.g. +13.5** and +17** dB)
* The default test configuration applies Line Loss. This can be overridden if the pva_rx_10 command is executed
from PowerShell, for example if testing a service outlet, where there is already some significant line loss present.
** Subtract 2 dB for PVA-3102 version 1 or 2 hardware.
When the pva_rx_10 test is run with Link Monitor, the monitor operates in a “Link Check” mode where the result for
each impairment condition will be either “UP” or “DOWN”. As discussed earlier in Section 1.3.12, Link Stability
measurements are not likely to be indicative of potential packet loss given a 10BaseT link where there is no option for
DUT to drop back to a lower rate and no real motivation to stop sending link pulses because of an impaired receiver.
Link Monitor measurements are computed based on a total of 400 Link Monitor samples collected over a 20 elapsed
second period. To return the “UP” condition, 99% or more link samples taken while the link is impaired must report
as “Linked”.
When the test method is Packets, 128,000 64-byte packets will be transmitted at line rate and packets are received and
counted on the “calibration partner” test port. The bridging function that is forwarding packets in the DUT is re-
primed after each new connection and after each impairment condition is introduced. Packet flow is reported as the
percentage of packets successfully transmitted.
Measurement results are displayed in a tabular form with a 3-level scale indicating “Limited”, “Good”, or “Excellent”
performance as shown below in Section 5.5. “Excellent” performance typically means that the receiver is operating
well beyond the minimum requirements of the 802.3 specification.
5.4.2. 100Base-TX Receiver Test
The 100BaseTx receiver test, pva_rx_100, will evaluate each connection polarity supported by the DUT. If the DUT
is MDI only, then only the receiver connected to pair 3 is tested and if it is MDI-X only, pair 2 is tested. If the port is
auto-MDI, then all testing is performed on both pair 2 and pair 3 (MDI-X and MDI modes).
The impairments utilized for each connection polarity during the 100BaseTx receiver test are:
Line Loss* + Low Transmit Level + Low Slew Rate
Line Loss* + Transmit Frequency Offset (+50 and +100ppm)
Line Loss* + Random Noise (e.g. +5 and +11 dB) where 0 dB Noise = 40mV
pk-pk
Line Loss* + Random Jitter (e.g. +10.5** and +16** dB) where 0 dB Jitter = 1.4nsec
pk-pk
Line Loss* + Random Noise (e.g. +4 and +10 dB) + Random Jitter (e.g. +9.5** and +15** dB)
* The default test configuration applies Line Loss. This can be overridden if the pva_rx_100 command is executed
from PowerShell, for example if testing a service outlet, where there is already some significant line loss present.
** Subtract 2 dB for PVA-3102 version 1 or 2 hardware.