I have quite a few mini-PC that has only a single gigabit port. I’ve been considering and researching how to expand those to have an extra port. One of those option was using a USB to Ethernet adaptor.
Now, I’ve looked at this option before. Ang nakuha ko lang puro discouragement na hindi siya stable.
Why it’s not recommended
- Doesn’t offload all processing from the CPU, causing high CPU usage
- Additional USB abstraction compared to PCIe
I found this thread, they discussed different chipsets and they benchmarked it too:
CDC – Communication Device Class (USB)
NCM – Network Control Model
A CDC NCM compliant device exposes itself as a virtual NIC to the host operating system.
A CDC ECM is a predecessor of NCM that needs software implementation of other Ethernet standards, causing high CPU usage during transfer.
AX88179A: Bus: USB Vendor Name: ASIX Product Name: AX88179A Vendor ID: 0x0b95 Product ID: 0x1790 USB Link Speed: Up to 5 Gb/s Driver: com.apple.driver.usb.cdc.ncm BSD Device Name: en4 MAC Address: 20:7b:d2:11:a4:e3 AVB Support: No Maximum Link Speed: 2.5 Gb/s
- CPU heavy without driver on Mac. Driver: https://forums.macrumors.com/threads/macbook-air-usb-c-ethernet-unreliable.2287743/post-31123118
- AX88179 is different to AX88179A. The A at the end indicates macOS support using CDC NCM driver.
- Does not support VLAN with native CDC NCM driver
Another recommended chipset is Realtek RTL8156B
Recommended chipset: RTL8153
Issue with AX88179: starts not active. Solution is to create a bridge.