Early adopters: Plans for better usability of Intel usb4stream technology in Fedora?

Ask Fedora
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1

There’s one feature that will soon become available with kernel 7.2 that’ I’m looking forward to: and its Intel Introducing USB4STREAM Protocol For Linux - Opening Up Some Nifty Uses For USB4 (Phoronix)

This is a rapidly evolving area; documentation is still sparse. So a brief update on what it is:

  • USB4STREAM is a Linux feature that enables host-to-host data transfers over USB4/Thunderbolt cables with a minimal device interface (essentially /dev/tbstreamX) and relies on a kernel driver (thunderbolt_stream) and ConfigFS for configuration.
  • It aims to let standard file-like tools (dd, tar, gzip, cat) stream data directly between machines without networking or SSH, once properly configured.

it reminds me a COM port link from 1990s, but on steroids. Actually this should have been available since the early days of USB, but for some reason it’s being born only in 2026.

One of the primary use cases would be Backup and tooling options, also file synchronization between devices.

Conceptually, you can use standard streaming tools to move data between hosts once a stream is configured, enabling backup-style transfers without network stacks (no IP address needed). This means dd, tar, or rsync over a /dev/tbstreamX-like path could work in the right environment, but you’ll need the proper kernel support and a ConfigFS-based setup to establish the streams.

As of the current information, ready-made backup tools specifically targeting USB4STREAM are not matured, but new wrappers and disaster-recovery integrations are anticipated as the kernel support lands in more distros.

Another area could be cross-device screen sharing (a la google cast).
And many more… like: cloning/migrating existing Fedora install to a new laptop over USB, etc…

At the end of the day, this seems like a major innovation making many great new possibilities possible.

As this is a bare bones link, anyone using command-line tools and scripting will be able to use it right away. If i get it right, it needs ConfigFS setup to configure streams under /sys/kernel/config/thunderbolt/stream/ to create HopID-based streams, then access the stream via a device like /dev/tbstreamX. Initial experiments will involve simple data transfers with dd or cat between the two ends.

I’m wondering if fedora team is thinking in adopting this and maybe contributing to better usability of this link?

2

You cannot connect two computers with USB electrically.
So it is not possible, try and you see smoke…

Only usb-c/thunderbolt allows for the electrical connection to be made.

3

Firewire could do it back in the day, but it ended up being squeezed out by USB…

4

The old powerbook macs had a mode in the firmware to be a firewire server. Great for fixing a broken system or transfering to a new laptop.

5

There are some ‘USB data link’ bridge cables available, but they must be purchased separately. And I don’t know a single person over the years who’s tried one.

also, hopefully usb4stream will become available as a software update for android devices, then, finally, other (older) laptops and tablets will easily be converted to spare external monitors and servers/NAS at the same time when needed.
easier LAN parties (most laptops have 2 usb-c ports), local p2p networking (especially if your government shuts down your internet…) The technology looks very promising.

6

That is not a direct connection.
It’s a device that presents to each computer as something it can electrically and protocol wise connect to.

I’m sure you have the USB cables that have a square plug at one end and the rectangle plug at the other. That choice of two types of plug is specifically to prevent you connecting to computers directly together and causing a electrical fault.