USB Ethernet Adapters are a handy way to add an extra network interface to your computer – particularly the Intel Compute Stick, which doesn’t have an onboard Ethernet network adapter at all. However, what if you want to access multiple VLANs via this USB Network Adaptor? Is it possible? This article shows how we setup multiple VLANs on Windows 10 with a Realtek-based USB Ethernet adapter.
It’s seemingly a question without an answer. How can I connect to multiple VLANs via a single USB Ethernet adapter on Windows 10?
Some USB Ethernet adapters have VLAN support – but only allow you to communicate on one at a time. Others don’t have any VLAN support at all. This is very driver dependant – it’s not really up to Microsoft to provide this functionality on each adapter.
The answer is Realtek-based chipsets, and the Realtek PCI Diagnostic Program for Win7/Win8/Win10.
Running the Realtek PCI diagnostic utility presented a dialog to create multiple ‘virtual’ adapters, each assigned their own VLAN tag. The standard Realtek USB diagnostic utility didn’t contain these features, but the PCI utility did (even though we were using a USB adapter).
From this config utility, you can select the physical adaptor in the left hand side, and then select the ‘VLAN’ config option to view, create, edit and delete VLAN connections.
When you create VLANs, the main adaptor in Windows no longer has an IP address, but new virtual adaptors are created and these each have IPv4 and IPv6 config – allowing them to get an IP address on their respective tagged VLAN.
Make sure you tag the port on your network switch with the correct VLANs, so the adapter can communicate with the network. In Cisco terminology, you need to set a port as a ‘trunk’ port, and then whitelist the specific VLAN numbers allowed via that port.
In this example, port GigabitEthernet1/0/4 is allowed to communicate on VLAN Tags 1, 2 & 3. Ports 1, 2 & 3 are only allowed to communicate on one VLAN each.
If you don’t tag the port correctly, the data may be dropped or put onto the ‘default’ VLAN.
One practical way to use this functionality is running AirServer on an Intel Compute Stick, connected directly to a TV, and making AirPlay and Chromecast available on multiple WiFi networks. We are achieving this by connecting each WiFi network to a distinct wired VLAN, available on these Compute Stick devices via a USB Ethernet adaptor. AirServer advertises on all network adaptors it can find on the PC. With a bit of network topology planning, you can make this work really well to make video streaming & screen sharing accessible to all users on multiple WiFi networks.
Miracast doesn’t work as it relies on ‘peer-to-peer Wi-Fi Direct’ technology for discovery, which obviously doesn’t work on a wired LAN.
Huge thanks to James Eden who did much of the leg work to make this happen for a project we’re currently working on.