By default uses CDC-NCM, but can use ECM/RNDIS by changing the USE_ECM define from 0 to 1 in tusb_config.h
The Pico assigns itself an IP of 192.168.7.1 and a DHCP server is started that assigns the host computer 192.168.7.16. You should be able to ping the Pico from the computer to confirm the connection.
I've used the DHCP server code from the Pico examples rather than the TinyUSB one, but feel free to switch it out as needed.
No additional libraries other than those included in the Pico SDK are needed. Only the built-in TinyUSB and lwIP are used.
I have tested this on Windows 11 and iOS (CDC-NCM only), and I am aware of it working at least in Linux. I would hope it will work for MacOS and potentially Android too. I've only run it on a Pico W (RP2040) so far (though works when compiled as a Pico). I've not tested it on a Pico 2 / RP2350 yet, but since only the SDK is used it should be ok?
For Pico W, if you need to use CYW43-specific functionality, after adding cyw43_arch_init() call usb_network_init(...) with the last parameter (init_lwip) as false to avoid re-initialising lwIP again.
If you use the e.g. pico_cyw43_arch_lwip_poll library in CMakeLists.txt then you can remove the pico_lwip* libraries in this example (as they'll be linked anyway).
mDNS should work too if you want to use e.g. usbnet.local for the Pico rather than 192.168.7.1.
If you access stdio over the default UART connection, sending the 's' character will demonstrate a clean shutdown.
This is only meant as a starting point for your own projects!
The code was mostly based on the latest version of the TinyUSB webserver example: https://github.com/hathach/tinyusb/tree/master/examples/device/net_lwip_webserver with the hathach/tinyusb#2829 PR included (thanks for that!)
httpd_init() call) for simplicity, but this and anything else that can run under lwIP should work the same though the USB interface.