Put your test tool in the path, then switch it out.
Keep the bench wired while you select a direct Ethernet connection or your existing inline test platform. USB-controlled Gigabit bypass with power-loss fallback.
Overview
EtherShunt is a four-port Gigabit Ethernet bypass switch for inserting and removing a compatible external test platform from the physical network path. After initial installation, select the direct path or the tool path over USB-C serial without recabling each test. Power-loss fallback restores the bypass path; an armed and serviced watchdog can also return to bypass if the control host becomes unresponsive. Path changes interrupt traffic and require link renegotiation and application recovery.
- ✓4× Gigabit Ethernet Ports (W1, W2, E1, E2)
- ✓USB-C Powered & Controlled
- ✓Hardware Fail-Safe Signal Switch: auto-bypasses on power loss
- ✓Watchdog Timer: auto-bypasses on host timeout
- ✓Ultra-low Power Consumption
- ✓Serial Interface (USB CDC) for SET / UNSET commands
In Practice
Establish a direct-path baseline, insert your test equipment, run the experiment, then return to bypass before servicing the tool. EtherShunt works independently of FID with a compatible two-interface platform. It selects the physical path; the external tool supplies traffic forwarding, capture, analysis, or intervention.
- Repeat path selection without recabling for every test run
- Bypass the tool before a reboot, update, or baseline check
- Include USB serial control in your own test procedure
- Measure end-to-end recovery after every path change
Illustration of path selection, not a timing measurement. Every physical transition interrupts the link; allow for renegotiation and application recovery.
How It Works
Install During an Approved Interruption
Break the existing Ethernet link and connect the original endpoints to W1 and E1. In UNSET (bypass), EtherShunt connects W1 directly to E1. Verify the application baseline.
Connect Your Test Platform
Connect the compatible, forwarding-ready test platform to W2 and E2. USB-C provides power and serial control. FID is optional.
Select the Path and Verify Recovery
Use SET to route through the test platform or UNSET to restore the direct path. Each transition interrupts the link; allow renegotiation and verify application recovery before continuing.
Automatic Fail-Safe
On loss of power, the relay circuitry restores the direct physical path between the original endpoints. Relay switching time is not network recovery time: the endpoints still need to renegotiate the link, and the application may need additional time to recover.
For a host that remains powered but becomes unresponsive, arm and service the watchdog before the test. Validate both fallback mechanisms and end-to-end recovery on your actual equipment; bypass is not a guarantee of uninterrupted production operation.
Watchdog Timer
For a host that remains powered but becomes unresponsive, arm and service the watchdog before the test. Validate both fallback mechanisms and end-to-end recovery on your actual equipment; bypass is not a guarantee of uninterrupted production operation.
Arm the watchdog over the serial interface before beginning analysis. Once armed, EtherShunt issues a challenge number on the serial link at a configurable interval. Your host must reply with that number incremented by one before the timeout expires. If a valid response is not received, EtherShunt transitions to UNSET. Verify link and application recovery before continuing.
Port Layout
W1 and E1 connect to the two original network endpoints. W2 and E2 connect to the analysis host's two network interfaces. USB-C provides both power and serial control.
A Note on Link Renegotiation
Each transition physically moves the signal path, disrupting the link for a few milliseconds. The PHYs on each side then renegotiate the link state. This typically takes 1–3 seconds. During this window, traffic is interrupted.
Link renegotiation does not establish application recovery. After the link is re-established, verify application recovery on your equipment and confirm that the interruption meets your test requirements. If your use case requires hitless transitions, contact us for other options.