But we need early adopters so we have people using the solution, finding and fixing problems, and helping to spread the word. What we deliver now might not include some KickStarter extras and will be higher priced than through the KickStarter project, but it will include all the components and will work with Fedora 17 Beta.

Hardware

Interested in getting your hardware now? If you’re in the USA, here’s what will work with Fedora 17 Beta:

	Plugable USB 2.0 Universal Laptop Docking Station with DisplayLink DVI/VGA up to 1920×1080, Audio, Ethernet, and 4 Available High-Speed USB 2.0 Ports	Product Details		$79.00
	Plugable DC-125 USB 2.0 Laptop Docking Station and Multiseat Thin Client – VGA up to 1440×900 / 1280×1024, Audio, 2 USB ports	Product Details		$64.95

Note the $79 version does not mention use as a thin client (it’s marketed for the laptop docking market), but it will work. And in the future and as part of the KickStarter project, we’ll have a UD-160-M model which is the same hardware, but with documentation tailored for the thin client / multiseat case.

International Shipping Options

If you’re outside the USA, we’re still working on expanding our options. Note that the UD-160-A is not sold on amazon.co.uk and the DC-125 sold there is not yet updated with Fedora support (we’ll let you know when it is).

So to reach the rest of the world, we’re offering a new option for international shipping of the DC-125 from the USA via USPS Flat Rate Priority. It’s the same price as in the USA ($64.95), but with an additional $16.95 shipping cost. Just visit the DC-125 page, and choose “more buying choices” in the lower right.

And look for the second option with “INTERNATIONAL SHIPPING AVAILABLE”.

Let us know if you have any trouble with payment through Amazon. This version of the DC-125 includes all the components purchased through normal channels, but without the extra color packaging — this is so it can fit in a $16.95 fixed-rate priority international shipping box.

If you’ve never ordered and had an item shipped from the USA before via the US Postal Service, please research the rules in your country. We declare the actual value of all items, so in some countries customs and/or VAT taxes are collected, and all of those are paid by the recipient once the items arrive in country. And also note that while every shipment will have a tracking number, the tracking is generally poor once the item has left the USA.

Software

You can download Fedora 17 Beta here. Must be the default version (GDM) and use the “install media” option at the top — live CDs don’t work yet because of the modifications needed.

Install F17 to the hard drive of an available machine. For 3-4 thin clients, you can use a spare older machine – we’d recommend a machine with 1GB RAM and 2 cores or 2 GHz or more, but anything that F17 will run on at all, will work.

The thin clients will only come up to a green screen at this point. A few pre-release fixes are needed:

1. Disable SELinux. Here’s how. Things will work now, but with some plug/unplug instability. To fix that …
2. Get our latest fixes in udlfb.
   • Get all latest fedora updates (so your kernel and kernel-devel headers are at the same version)
   • sudo yum install gcc kernel-devel
   • Get latest udlfb, compile and install. The following commands will do that:

     git clone http://git.plugable.com/webdav/udlfb/
     cd udlfb
     make
     sudo make install
     sudo depmod -a
     

3. make sure none of those steps reported errors (missing module dependencies are actually ok). Reboot.

Now, any Plugable UD-160-A/M or DC-125 thin client you plug in should automatically pop up a new login.

Comment here or email support@plugable.com if you have any trouble at all – we’d be happy to help! And thanks in advance to the early users who help find issues and spread the word about how cool this technology can be!

We believe this makes a lot of sense. It saves a lot of time and money. It lowers the environmental impact of computing.

The way we can make this truly compelling is with low cost USB thin clients and zero software licensing fees. So we’ve launched a KickStarter project to try to push this concept over the finish line.

We’d love to have you involved! Visit the Plugable Thin Client on KickStarter to learn more.

And to hear what others are saying, check out:

• Quentin Stafford-Fraser, Founder of DisplayLink and Ndiyo, and his thoughts on the Plugable Thin Client
• Michael Larabel, of Phoronix.com, and his experiences using the Plugable Thin Client.
• Lennart Poettering of Red Hat, on the work to enable automatic USB multiseat in Fedora 17

Last year, he demoed turning your router into a full-fledged computer.

This year, it’s the Google Nexus One phone as a full computer — with attached external keyboard, mouse, display, and more.

The Nexus One demo is using the udlfb Linux kernel module to talk with the DisplayLink device, and it will work with any DisplayLink device, including Plugable’s.

Note the version of udlfb in the 2.6.34 staging tree unfortunately didn’t work for Sven. So he’s now using the latest udlfb from http://git.plugable.com/, which will likely get merged in for kernel 2.6.36.

Also, he used a dual headed cable to get enough power. A powered hub or a docking station/terminal like the UD-160-A won’t need that — it supplies its own power from AC – all the hardware needed is in the one package.

It’s exciting to have all this open source work come together in interesting demos like this.

There was a question recently why udlfb doesn’t use the same compression technique as the Windows drivers. Among other reasons, one is that the RL compression used by udlfb scales down to devices like the ones Sven has been working on — it’s as light as possible on CPU load, while getting decent compression.

Stepping back, it’s clear Apple (and now Microsoft) are making a mistake by limiting the hardware ecosystem around their devices. Android and the other Linux variants have an opportunity here — and considering the Apple juggernaut, they definitely need every advantage.

Sven’s demos show how powerful these scenarios can be. The hardware is ready. Devices like Plugable’s are designed with these scenarios in mind. Now we need to get the software refined and included in standard distributions, so normal consumers can take advantage of all the possibilities and benefits here.

We’re very excited about the Google funded project to refine USB multiseat on Linux, with the winning proposal from Lucas Nascimento Ferreira at the Federal University of Parana in Brazil.

In addition to providing mentoring, Plugable is also providing donated hardware for this project. Two Plugable Universal Docking stations with recent enhancements for use as a terminal, were just picked up by Lucas in Brazil today. By next month, we expect to have updated versions of the UGA-125-HUB for terminal use to send down.

For those interested in learning more and potentially following Lucas’ work:

• Google’s SoC 2010 Timeline
• Lucas’ winning USB Multiseat Proposal

And we’ll post periodic status updates here.

Linux hasn’t had that support — it would try to set the highest mode the monitor is capable of, often resulting in a black screen. Especially common for the DL-125 chip, with its mode limits of 1440×900/1280×1024.

That’s a shame because the DL-125 chip is a smart choice in many cases – by limiting itself to those lower modes, it stays more consistently within the limits of the USB 2.0 bus, resulting in more consistent performance.

So coinciding with the launch of Plugable’s DisplayLink DL-125 based products (UGA-125 and UGA-125-HUB), changes have been implemented to bring Linux roughly up to the level of Windows and Mac in this area for DisplayLink devices. This also helps devices like the UD-160-A when running on monitors greater than its limit of 1920×1080.

The kernel framebuffer driver udlfb has been enhanced to read the resolution limit from the firmware descriptors of the device, and adhere to it.

On the X server side, we needed a driver which would limit itself to the resulting reduced mode list. Unfortunately, the existing displaylink X server reads EDID directly, and assumes the adapter can do whatever the monitor can do.

We’ve been wanting to get rid of the need for a displaylink-specific X server, and the standard xf86-video-fbdev driver runs with the best existing mode, rather than trying to set a higher one in EDID. So this was a good trigger for converting over.

So xf86-video-fbdev has been enhanced with X Damage protocol support, ported from Roberto’s displaylink driver. This is still a little in-flux from an interface perspective, but from a functional perspective it’s done and fully performant.

So it’s now possible to run with a modified generic fbdev driver, which talks to udlfb, with full performance and without needing defio (although there’s also some good news in the defio space, which will be posted about later).

You can grab the latest udlfb kernel module with a “git clone http://git.plugable.com/webdav/udlfb”. Compile with “make && sudo make install && sudo depmod -a”

And you can grab the latest modified xf86-video-fbdev with a “git clone http://git.plugable.com/webdav/xf86-video-fbdev”. Compile with “./autogen.sh && make && sudo make install”

You’ll need a very recent xorg-macros version (1.4), which in package “sudo apt-get install xutils-dev”

To use the new X server, you must turn on the new “ReportDamage” option to fbdev. Modify your existing xorg conf like this:

Section "Device"
  Identifier "dl"
  Driver "fbdev"
  Option "ReportDamage" "true"
  Option "fbdev" "/dev/fb0"
EndSection

And you should be all set to go. This new X server should work with the existing udlfb in the staging tree of kernel 2.6.31+ for now, as it’s re-using the same original ioctl. But may require modeset changes that are only in 2.6.34+.

The main focus is USB multiseat, and the details are on the xorg wiki for SoC 2010

With all the pieces that are just coming together now, there is a potential here to do a project with huge impact, without a massive amount of engineering. There is already a very solid proposal coming from a student in Brazil who has previously been involved with the MDM multiseat project.

Google’s deadline for applications is now just a few days away: April 9th.

If there’s interest from other parties, we’ll get everyone talking – or there are other related proposals that we might be able to get in at the last minute. Foremost among those is conversion of the DisplayLink USB driver udlfb and matching X server from a fbdev driver to the KMS model.

Here’s the basics of the USB multiseat opportunity:

USB Multiseat Refinement

Linux Multiseat setups have potential to significantly reduce the cost of computing, but can be hard to configure. Some progress has been made on USB multiseat, where all components of the “terminal’ (display, keyboard, mouse, and more) are on USB, so configuration can be fully plug and play – you can just assume that all devices on the same USB hub constitute a terminal.

Some early prototypes of this are working (see http://plugable.com/2009/11/16/setting-up-usb-multiseat-with-displaylink-on-linux-gdm-up-to-2-20/). The underlying kernel drivers and X servers are largely in place.

But recent changes to the X Server, ConsoleKit, and other components open the possibility for a cleaner implementation.

This SoC project would constitute the refinement/creation of configuration scripts to enable a standard Linux or *nix computer to automatically launch additional seats when a USB terminal is plugged in

* udev rules to detect hubs/devices which should be collectively treated as terminals
* udev attributes to label the set of devices with a common seat id
* udev triggers for on-demand generation of the appropriate Xorg config files, to allow seats to coexist with the primary display/devices.
* ConsoleKit scripts to launch independent GDM/X sessions for each USB terminal seat
* InputClass rules to cause the primary X session to ignore multiseat-assigned devices, and the appropriate seat to use them
* udev rules and X init scripts to grant access to audio, storage, and other devices to the person logged into the matching seat

The one-sentence goal of this project: To make USB multiseat fully plug and play for the end-user, and ready for any distro to safely and cleanly drop in at any time.

Know any aspiring software engineering students that might be interested? Check SoC info from Google and the SoC guidelines from xorg.

There will still be some bugs and issues to resolve — but this release has most of the features, specifically related to input handling and udev-based dynamic configuration, of a more solid USB multiseat solution.

In short:

• udev rules, which already can detect a grouping of USB devices that constitute a terminal, can now tell X to ignore or use particular devices more easily through udev attributes and more dynamic/independent xorg.conf.d scripts.
• udev is now the default configuration mechanism (the torch has been passed from the less flexible hal)

So the challenges to explore are now more in the area of ConsoleKit integration and whether we can use these new capabilities support not just pure-USB multiseat setups, but also a mix of seats with PCIe attached graphics, and with fully USB seats.

You can read more about the new 1.8 configuration features which multiseat will use at Peter Hutterer’s blog.

And read more about the RC itself at Phoronix

Add the following line to the bottom of the /lib/udev/rules.d/50-usbseat.rules file created per the previous instructions.

KERNEL=="control*", SUBSYSTEM=="sound", SUBSYSTEMS=="usb", PROGRAM="/bin/cat /sys/%p/../../../../../devnum", SYMLINK+="usbseat/%c/sound"

Then create a new /etc/X11/Xsession.d/50usbseat file which will be run at Xsession create time, with the following contents

oldIFS=$IFS
IFS=:
set $DISPLAY
IFS=.
set $2
SEAT_ID=$1
LN=`ls -al /dev/usbseat/$SEAT_ID/sound`
IFS=C
set $LN
CARD_ID=$2
export ALSA_CARD=$2
export ALSA_PCM_CARD=$2
IFS=$oldIFS

Each of the users who might need access to the USB devices needs to be added to the ‘audio’ group. On Ubuntu 9.04, this can be done with these commands to backup and then modify the groups (replace MY_USERNAME, of course) …

sudo cp /etc/group /etc/group_backup
sudo chmod a-wx /etc/group_backup
sudo adduser MY_USERNAME audio

See Ubuntu Sound TroubleShooting for details on that step.

Now, as you connect UD-160-A terminals, a new X instance and GDM login will pop up as before, but also each of them will have /dev/usbseat/%SEAT_ID%/sound linking to their sound device, and the ALSA_CARD environment variable for all processes off of that X session, set to the matching sound card ID. For apps which support ALSA/Pulse (like most browsers, flash, etc.), audio will now come out the correct terminal — all in a completely plug-and-play fashion.

If you’re wondering what the strange IFS stuff is in the above script, it’s bash’s built-in Internal Field Separator variable, which is an easy way to split strings without having to launch a separate sed or awk process.

Note, as before, these instructions are specific to and tested on an older version of Ubuntu: 9.04, and may need to be ported to other distros until the distros themselves integrate these scripts.

Thanks to Alexander Todorov’s earlier work on multiseat sound support, which demonstrated how to match the USB audio devices in udev, and which ALSA_ environment variables to set. Alexander reported some problems reliably matching the audio devices, but with these scripts (with limited testing so far), things are working as expected.