How does GMSL compare to USB and Ethernet for robotic vision?

GMSL (Gigabit Multimedia Serial Link) is becoming popular in robotics because it solves many problems that USB and Ethernet face.
As the demands on robotic vision grow with more cameras, higher resolution, tighter synchronization, and harsher environments, traditional interfaces like USB and Ethernet often fall short in terms of bandwidth, latency, and integration complexity.

The below table compares the three technologies across key metrics relevant to robotic vision design.

Feature/Criteria GMSL (GMSL2/GMSL3) USB (for example, USB 3.x) Ethernet (for example, GigE Vision)
Cable Type Single coax or STP (data + power + control) Separate USB + power + general-purpose input/output (GPIO) Separate Ethernet + power (PoE optional) + GPIO
Max Cable Length 15+ meters with coax 3 m reliably 100 m with Cat5e/Cat6
Power Delivery Integrated (PoC) Requires separate or USB-PD Requires PoE infrastructure or separate cable
Latency (Typical) Tens of microseconds (deterministic) Millisecond-level, OS-dependent Millisecond-level, buffered + OS/network stack
Data Rate 3 Gbps/6 Gbps/12 Gbps (uncompressed, per link) Up to 5 Gbps (USB 3.1 Gen 1) 1 Gbps (GigE), 10 Gbps (10 GigE, uncommon in robotics)
Video Compression Not required (raw or ISP output) Often required for higher resolutions Often required
Hardware Trigger Support Built-in via reverse channel (no extra wire) Requires extra GPIO or USB communications device class (CDC) interface Requires extra GPIO or sync box
Sensor Aggregation Native via multi-input deserializer Typically point-to-point Typically point-to-point
EMI Robustness High—designed for automotive EMI standards Moderate Moderate to high (depends on shielding, layout)
Environmental Suitability Automotive-grade temp, ruggedized Consumer-grade unless hardened Varies (industrial options exist)
Software Stack Direct MIPI-CSI integration with SoC OS driver stack + USB video device class (UVC) or proprietary software development kit (SDK) OS driver stack + GigE Vision/ GenICam
Functional Safety Support ASIL-B devices, data replication, deterministic sync Minimal Minimal
Deployment Ecosystem Mature in ADAS, growing in robotics Broad in consumer/PC, limited industrial options Mature in industrial vision
Integration Complexity Moderate—requires SERDES and routing config Low—plug and play for development High—for production Moderate—needs switch/router config and sync wiring

This makes GMSL a better choice for advanced robotic vision systems compared to USB and Ethernet.

Related Article:
Can GMSL support multiple cameras at once?
Why does Power over Coax (PoC) matter for robots, and how does GMSL use it?
How does GMSL solve the problem of bandwidth and latency?
Why are modern robots using more cameras than ever before?
What types of robotic systems benefit most from GMSL technology?
What is GMSL and how it is enhancing robotic vision systems?