A report from SCALE 2008

Escaping the cold for 70 degree days in Los Angeles might be a reason for some—Colorado-based LWN Editors for example—but it clearly is not the reason that most folks choose to attend Southern California Linux Expo (SCALE). Many of the approximately 1400 attendees already live in the region, so it is the speakers, participants, and the expo floor that bring them in. I attended the sixth annual SCALE (SCALE 6x), just held, February 8-10 and it didn't take me very long to see why it continues to grow and prosper.

SCALE is a three day event, with two main conference days on Saturday and Sunday and a set of mini-conferences running in parallel on Friday. Each mini-conference covers a focused topic of interest to the community, with this year's topics examining Women in Open Source (WIOS), Open Source Software in Education (OSSIE), and Demonstrating Open Source Healthcare Solutions (DOHCS). It was a full day as each had eight or more hour-long sessions.

Allison Randal kicked off the WIOS track with a presentation aimed at encouraging more women to give presentations at conferences. Her talk, "The Art of Conference Presentations", was not particularly gender specific, of course. It covered the process of proposing, creating and giving talks to conferences. Randall's advice was cogent, from avoiding "cute" titles to establishing credibility via your biography without feeling like you are bragging. Her most important point was to not wait around until you are the perfect speaker, but to go out and start speaking; your voice and style will come with practice.

Over in the OSSIE track, Dan Anderson related his experiences teaching computer science concepts to middle and high school students over the last fourteen years. His approach is to use computing as a bridge between math, science, and technology. He discussed the process of creating, or trying to create, a stable curriculum in the face of rapid technological change. Because the hardware, operating systems, and languages all change quickly, his courses need to focus on concepts that are not specific to any of those. Over the years he has taught, the language used in the advanced placement course—dictated by the state CollegeBoard company—has gone from Pascal, through C++, and now uses Java, with some rumblings being heard about moving to Python. As he points out, "much of what a High School student learns about technology will be outdated by the time they graduate from college".

He uses How to Design Programs as the core text for his courses. It uses a graphical programming environment called DrScheme, which is based on Scheme, that allows different subsets of the language to be used based on the skill level of the student. Anderson has integrated various peripherals, like cameras and audio equipment, into the environment so that students can interact with the real world in interesting ways. His students work on projects like voice authentication and computer vision; this year's project is to recognize tic-tac-toe as drawn on a white board.

Other topics from OSSIE included a tutorial introduction to the moodle content management system (CMS) for online learning. Much like other CMS projects, moodle allows the creation of websites with various kinds of content—audio, video, images, and text—but organized as a course. It provides a framework and philosophy to guide the development of online classes. Students access the content via the web, completing tasks, taking quizzes, and participating in forums and chats with other students.

Charles Edge (no relation) spoke about the challenges of implementing directory services for educational institutions. One problem is that the term "directory services" cover a large amount of ground, from tracking users (both employees and students) to allowing single sign-on (SSO) into multiple machines and services throughout the school. The biggest challenge can be handling the sheer numbers of people to be tracked. Open source solutions do exist, OpenLDAP for storing the information, Kerberos for single sign-on and Simple Authentication and Security Layer (SASL) for extending the reach of the SSO into other services, but it is complex to configure and administer. For scalability and robustness in large installations, Edge suggests Microsoft's Active Directory, which was not a particularly popular opinion with the open source oriented audience.

The first day closed with a WIOS panel discussion, where six of the women presenting or showing at the conference discussed the issues facing women in open source. The discussion was informal and wide-ranging with a great deal of audience participation. Audience members asked questions as well as offered opinions and theories on why the participation of women is low and what can be done to make things better. No real conclusions were reached, as is usual for discussions of this topic; it is one of the more puzzling attributes of the free/open source community.

The animated and amusing Ubuntu community manager Jono Bacon gave a rousing keynote to start things off on Saturday. He tried to ensure that everyone was awake by leading a greeting in multiple languages (including Klingon). His main point was to describe the responsibilities of the various "factions" that jockey to determine the future of open source software—companies, distributions, and communities—trying to show that each has an important role. In fact, it is up to all constituents to ensure that the greater Linux ecosystem thrives and that each group works well with the others. It was all pretty much "motherhood and apple pie" stuff, but well described and illustrated—all with Chuck Norris to keep track of the score. Bacon did provide the quote of the show when he said that free software was "started by a guy with a beard who was pissed off at a printer".

Saturday was also the first day that the expo floor was open. Some 80 booths were there, representing companies large and small as well as lots of free software projects. One of the more interesting booths contained a working simulator of a 747 cockpit. All of the instruments were driven from a realtime Linux box and the FlightGear flight simulator was used to generate the cockpit window view. The two machines communicated over the network and various laptops were able to view the flight from other perspectives by getting updates from the simulator. It was rather impressive.

The linuxastronomy.org project was also on hand with their telescope prototype. The telescope will be controlled via a Linux machine allowing it to be pointed at locations as specified by users. A Linux desktop application will send locations to the telescope over the internet, allowing it to be remotely controlled so that it can be installed in a mountaintop or other location with (relatively) little light pollution and good viewing conditions. In addition, the project was demonstrating many of the free astronomy programs available for Linux.

A mobile audio studio product, Indamixx, did not have a booth, but could be seen all over the show. The company loaned two of the UMPC-based devices to the conference which were used to do podcasts of interviews with speakers and attendees. The device runs Linux with Audacity and ardour along with other free software. The company has tweaked things to make it all work well and be easy to use on the device. It looks to be quite capable as well as easily portable.

In another interesting talk, David Maxwell of Coverity gave an update on their project to scan free software for security holes. The US Department of Homeland Security gave Coverity a grant to work with free software projects to use the Coverity Prevent static code analysis tool (once known as the "Stanford Checker") on the code. The scan project has found over 7,000 defects in around a hundred free software projects since its inception. Maxwell is the Open Source Strategist for Coverity; he is looking for more projects to participate. He is encouraging any free/open source software project to get in touch with him to get signed up for the program.

Projects that join get their code scanned with a report being generated on the Coverity website for project members to view. The projects can then fix any of the issues that are actually bugs, mark others as "not a bug", and resubmit the code. The Coverity system will check the latest code out of their source code repository and check it again. Once all issues that the tool finds are handled, the project can move up to a higher "rung on the scan ladder" which will allow them to be scanned by more recent versions of the Coverity tool.

Bdale Garbee had perhaps the geekiest talk of the show on Saturday afternoon with "Open Avionics for Model Rockets". Garbee gave an overview of the hobby, which has gone far beyond the Estes rockets that many of us dabbled with in our youth. These rockets can go to 10,000 feet and above; just how high they go is one of the questions that led folks to start outfitting them with instruments. Deploying the recovery system—typically a parachute—at apogee is very desirable and a barometric sensor with a little bit of logic tied to the ejection charge can do just that. Unfortunately, all of the commercially available options for these systems are completely closed; even the protocol to talk to the device is not released by the manufacturers.

Garbee decided to once again combine one of his hobbies with open source to design and build an open device. Both the hardware and software will be released under free licenses (GPL and Open Hardware License); he had version 0.1 of the hardware (missing the accelerometer due to a problem in the board layout) with him at the show. The AltusMetrum system also has an onboard barometric sensor and will be able to support things like GPS devices and radio transmitters—so that lost rockets do not stay lost. Garbee expects to flight test the board and design version 0.2 of the hardware over the coming months.

Sunday's keynote, by Stormy Peters of OpenLogic was entitled "Would you do it again for free?". Peters looked at whether external rewards, usually money, affect the motivation of open source developers; in particular, if the pay stops, will the project work stop as well? She cited four separate "studies" (including two that weren't intended as studies) that seemed to show that adding a reward, or penalty, can sometimes have a counter-intuitive effect (see an entry in her weblog for more information).

Peters came to no firm conclusions about what the long-term effects of paying open source developers would be, but there are some mitigating factors that seem to provide hope that developers would continue if the paychecks stopped. When a payment or reward is in line with expectations for doing a particular task, it is much less demotivating. Also, if the payment is for working on the project, not tied to a specific goal or milestone, it is also less of a problem. Both of those are typically the case with folks who are paid—40% of open source developers are, according to Peters—for their work in the community.

After a last wander through the show floor, I was able to catch a few minutes of the talk given by Ken Gilmer and Angel Roman of Bug Labs describing their modular embedded Linux gadget building system. The system consists of a core module along with various plug-in devices: camera, motion detector, GPS, etc. that can be combined into a single Java programmable device. Many additional peripheral modules are planned. The software that runs on the device is free and Bug Labs has a community site to share application code; they are clearly hoping that they can foster a community of users and developers.

As can be seen, SCALE offers a wide variety of technical content in a well organized and fun conference. It has grown beyond the capacity of the Airport Westin where it has been held for the last few years; expect a new, bigger venue somewhere in LA next year. Over the last few years, SCALE has drawn from more areas of the southwest US in moving from a small, local conference to a regional one. If things continue, in another few years it may grow into a national conference; one can only hope that if that happens, it will continue to be as well run and interesting as it is today.