PVA-3000 Reference Manual
December 2, 2019 Sifos Technologies
When the pva_rx_100 test is run with Link Monitor, an initial assessment is performed on the DUT to determine if it
ever drops link (i.e. stops transmitting 100BaseTx IDLE) given a very severe receiver impairment that would for
certain lead to 100% packet loss. If it is determined that the DUT link was not permanently down in this condition,
then Link Monitor will operate in a “Link Check” mode as it does for 10BaseT testing and the result for each
impairment condition will be either “UP” or “DOWN”. To return the “UP” condition, 99% or more link samples taken
while the link is impaired must report as “Linked”.
If on the other hand the DUT does drop link in response to highly impaired receiver performance, then it is more likely
that a Link Stability measurement could approximate a hypothetical packet loss measurement and Link Stability will
be reported as 0 to 100%. All Link Monitor measurements (Link Check or Link Stability mode) are computed based on
a total of 400 Link Monitor samples collected over a 20 elapsed second period.
When the test method is Packets, 1,024,000 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.
5.4.3. 1000BaseT Receiver Test
The 1000BaseT receiver test, pva_rx_1000, will evaluate a gigabit Ethernet receiver in both MASTER and SLAVE
timing modes with impairments that are selected according to the mode. If a DUT only supports one of those modes,
then only that mode will be tested. As was the case with 1000BaseT transmitter testing, in 1000BaseT, all four pairs
are always receiving so there is no need to modify connection polarity. However, there is the need to apply
impairments simultaneously to all four pairs thus reducing some of the asymmetrical impairment abilities used with
10BaseTand 100BaseTx receiver testing.
The impairments utilized with the DUT in the MASTER timing mode are:
Line Loss* + High Slew Rate
Line Loss* + Low Transmit Level + Low Slew Rate
Line Loss* + Random Noise (e.g. -1, +1.5, and +4 dB) where 0 dB Noise = 40mV
pk-pk
Line Loss* + Random Jitter (e.g. -1**, -1**, and 3** dB) where 0 dB Jitter = 1.4nsec
pk-pk
Line Loss* + Random Noise (e.g. -1.5, +1 and +3.5 dB) + Random Jitter (e.g. –1.5**, 0**, and +2** dB)
The impairments utilized with the DUT in the SLAVE timing mode are:
Line Loss* + Low Transmit Level + Low Slew Rate
Line Loss* + Transmit Frequency Offset (+100 and +115ppm)
Line Loss* + Transmit Frequency Offset (+100 ppm) + Random Noise (e.g. -1, +1.5 and +4 dB)
* The default test configuration applies Line Loss. This can be overridden if the pva_rx_1000 command is executed
from PowerShell, for example if testing a service outlet, where there is already some significant line loss present.
** Subtract 3 dB for PVA-3102 version 1 or 2 hardware.
When the pva_rx_1000 test is run with Link Monitor, the Remote Rx Status indictor is utilized (see Section 1.3.12) in
place of Link Status. This technique allows for a much closer approximation to packet loss performance than is
available with 10Base-T and 100Base-Tx testing. The Remote Rx Status indicator is an IEEE 802.3 required feature of
all 1000Base-T interfaces and therefore, there is no need to pre-qualify behavior under high impairments.
Using the Remote Rx Status indicator assures Link Stability will be reported as 0 to 100%. All Link Monitor
measurements are computed based on a total of 1000 Link Monitor samples collected over a 20 elapsed second period.
When the test method is Packets, 10,240,000 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
beyond the minimum requirements of the 802.3 specification and is on par with the state of the art in 10/100/1000Base-
T transceivers.
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