[USG Flex H Series] - PHY-based Virtual Cable Tester

Maverick87

Hello everyone,
I would like to suggest a new PHY-based Virtual Cable Tester/Time Domain Reflectometry diagnostics to the USG FLEX H Series.

Basically is so quite simple:

• Select the port/ports that you would like to check;
• The firewall check the selected ports and report:
  • Status:
    • Cable OK/Normal → When the connection is stable and success;
    • Short/Same-pair short → Short on same-pair couple
    • Short/Cross-pair short → Short on cross-pair couple
    • Impedance mismatch, if supported → Impedance discontinuity, for example a junction, a faulty crimp, or a damaged cable
    • Noise → Test disrupted by noise/interference
    • Unknown/Test Failed → The test is started but the result produced no valuable output
    • Unsupported → PHY/port not supported
    • PHY Unavailable/Driver failure → PHY not initialized or not associated to a driver
  • Cable length when the pair is OK
  • Distance to fault when an open or short is detected

The UI should clearly distinguish between:

1. A cable test that completed and detected an open circuit;
2. A cable test that could not be executed;
3. A PHY initialization or driver failure.

A PHY/driver failure must not be reported as “Cable Open.”
The raw driver error should be included in the diagnostic output and diaginfo file.

The UI should also warn that the test may temporarily interrupt an active link and that measurements below approximately 10 metres may be inaccurate.

Can be also interesting a debug/information button for every test/port, indicating for example:

Port: P2
Administrative state: Enabled
PHY state: Attached
PHY driver: mv88x2110
MDIO address: 01
Link state: Down
Autonegotiation: No partner detected

Cable test:
Pair A (pins 1-2): Open, 24 m
Pair B (pins 3-6): Open, 24 m
Pair C (pins 4-5): Open, 25 m
Pair D (pins 7-8): Open, 25 m

Estimated cable length: 24-25 m
Test confidence: Medium
Test duration: 3.2 seconds

or:

Port: P2
PHY state: Initialization failed
Driver error: -22 (EINVAL)
TDR test: Not executed
Cable condition: Unknown

Some of these feature are already implemented into the Zyxel Nebula switch:
https://mysupport.zyxel.com/hc/en-us/articles/30479023979410-FAQ-E-Understanding-the-Cable-Diagnostics-Status-of-Switches-on-Zyxel-Nebula