One of the most innovative features to find its way into the Linux kernel recently is support for master mode on several wireless chipsets.  Though there's been little fanfare surrounding this development, it could soon be giving home users, in particular, another reason to celebrate Ubuntu.

Until a few years ago, Linux's poor wireless support was one of the free-software community's greatest embarrassments.  Many devices lacked native support, meaning that the fickle process of loading Windows drivers through ndiswrapper was often the only way to get cards working--and even then, they were limited to managed and ad-hoc modes.

This situation has been completely reversed recently, with the Linux kernel now boasting at least basic support for most wireless cards, thanks to the Linux wireless project.  Although Ubuntu's rather conservative approach to the new wireless stack leaves many users still having to install drivers manually in Intrepid, the era is at least on the horizon when wireless networking will work out-of-the-box for everyone.

Master mode

Even better than a wireless card that "just works" in Ubuntu when connecting to a router in managed mode is one that can also replace the router, by operating in master mode.  As of April 2009, the latest drivers from the Linux wireless project support this functionality on the following chipsets:
  1. Atheros (newer chips only)
  2. Broadcom
  3. Intel (2200 chips only)
  4. Prism
  5. Ralink (except the newest devices)
Granted, only experienced Linux geeks are likely to be able to enjoy master mode for the time being, since putting it into action requires intimate familiarity with the 'iwconfig' command, the 'hostap' utility and most likely dhcp servers, not to mention bridging network interfaces together.

Nonetheless, the day has at least become conceivable when setting up an Ubuntu computer as a wireless router is as easy to clicking a button in NetworkManager, allowing even the most technologically inept Linux users to create local wireless networks effortlessly--and not just ad-hoc networks like those supported by 'Internet Connection Sharing' in Windows, but true access point-based networks.

Why it matters

Beyond being cool, the ability to turn an Ubuntu computer easily into a wireless router has practical benefits.  For starters, it saves consumers money, since they can avoid purchasing access points from commercial vendors.

A home computer turned into a router also offers much greater flexibility than most moderately priced commercial products.  Rather than being stuck with the limited number of settings made available by hardware vendors, users can route traffic, customize firewalls, log activity and so on in whichever way they see fit.

As driver developers continue to enhance the capabilities of wireless on Linux and surpass the offerings of proprietary operating systems, Ubuntu and other distributions should concentrate on making those features easily accessible to end users, and on promoting them as one more thing that Linux can do and closed-source software can't.