Reading around a variety of articles on the various ways of deploying software in education, it struck me that in traditional institutions a switch is may be taking place between students making use of centrally provided computing services – including physical access to desktop computers – to students bringing their own devices on which they may want to run the course software themselves. In addition, traditional universities are also starting to engage increasingly with their own distance education students; and the rise of the MOOCs are based around the idea of online course provision – that is, distance education.
The switch from centrally provided computers to a BYOD regime contrasts with the traditional approach in distance education in which students traditionally provided their own devices and onto which they installed software packaged and provided by their educational institution. That is, distance education students have traditionally been BYOD users.
However, in much the same way that the library in a distance education institution like the OU could not originally provide physical information (book lending) services to students, instead brokering access agreements with other HE libraries, but now can provide a traditional a traditional library service through access to digital collections, academic computing services are perhaps now more in a position where they can provide central computing services, at scale, to their students. (Contributory factors include: readily available network access for students, cheaper provider infrastructure costs (servers, storage, bandwidth, etc).)
With this in mind, it is perhaps instructive for those of us working in distance education to look at how the traditional providers are coping with an an influx of BYOD users, and how they are managing access to, and the distribution of, software to this newly emerging class of user (for them) whilst at the same time continuing to provide access to managed facilities such as computing labs and student accessed machines.
Notes from: Supporting CS Education via Virtualization and Packages – Tools for Successfully Accommodating “Bring-Your-Own-Device” at Scale, Andy Sayler, Dirk Grunwald, John Black, Elizabeth White, and Matthew Monaco SIGCSE’14, March 5–8, 2014, Atlanta, GA, USA [PDF]
The authors describe “a standardized development environment for all core CS courses across a range of both school-owned and student-owned computing devices”, leveraging “existing off-the-shelf virtualization and software management systems to create a common virtual machine that is used across all of our core computer science courses”. The goal was to “provide students with an easy to install and use development environment that they could use across all their CS courses. The development environment should be available both on department lab machines, and as a VM for use on student-owned machines (e.g. as a ‘lab in a box’).”
From the student perspective, our solution had to: a) Run on a range of host systems; b) Be easy to install; c) Be easy to use and maintain; d) Minimize side-effects on the host system; e) Provide a stable experience throughout the semester.
From the instructor perspective, our solution had to: a) Keep the students happy; b) Minimize instructor IT overhead; c) Provide consistent results across student, grader, and instructor machines; d) Provide all necessary software for the course; e) Provide the ability to update software as the course progresses.
Virtualbox was adopted on the grounds that it runs cross-platform, is free, open source software, and has good support for running Linux guest machines. The VM was based on Ubuntu 12.04 (presumably the long term edition available at the time) and distributed as an .ova image.
To support the distribution of software packages for a particular course, Debian metapackages (that simply list dependencies; in passing, I note that the Anaconda python distribution supports the notion of python (conda) metapackages, but pip does not, specifically?) were created on a per course basis that could be used via apt-get to install all the necessary packages required for a particular course (example package files).
In terms of student support, the team published “a central web-page that provides information about the VM, download links, installation instructions, common troubleshooting steps, and related self-help information” along with “YouTube videos describing the installation and usage of the VM”. Initial distribution is provided using BitTorrent. Where face-to-face help sessions are required, VM images are provided on USB memory sticks to avoid download time delays. Backups are handled by bundling Dropbox into the VM and encouraging students to place their files there. (Github is also used.)
The following observation is useful in respect of student experience of VM performance:
“Modern CPUs provide extensions that enable a fast, smooth and enjoyable VM experience (i.e. VT-x). Unfortunately, many non-Apple PC manufacturers ship their machines with these extension disabled in the BIOS. Getting students to enable these extensions can be a challenge, but makes a big difference in their overall impression of VM usability. One way to force students to enable these extensions is to use a 64-bit and/or multi-core VM, which VirtualBox will not start without virtualization extensions enabled.”
The open issues identified by the team are the issue of virtualisation support; corrupted downloads of the VM (mitigation includes publishing a checksum for the VM and verifying against this); and the lack of a computer capable of running the VM (ARM devices, low specification Intel Atom computers). [On this latter point, it may be worth highlighting the distinction between hardware that cannot cope with running computationally intensive applications, hardware that has storage limitations, and hardware that cannot run particular virtualisation services (for example, that cannot run x86 virtualisation). See also: What Happens When “Computers” Are Replaced by Tablets and Phones?]
The idea of using package management is attractive, and contrasts with the approach I took when hacking together the TM351 VM using vagrant and puppet scripts. It might make sense to further abstract the machine components into a Debian metapackage and a simple python/pip “meta” package (i.e. one that simply lists dependencies). The result would be an installation reduced to a couple of lines of the form:
apt-get install ou_tm351=15J.0
pip install ou_tm351==15J.0
where packages are versioned to a particular presentation of an OU course, with a minor version number to accommodate any updates/patches. One downside to this approach is that it splits co-dependency relationships between python and Debian packages relative to a particular application. In the current puppet build files for the monolithic VM build, each application has its own puppet file that installs the additional libraries over base libraries required for a particular application. (In addition, particular applications can specify dependencies on base libraries.) For the dockerised VM build, each container image has it’s own Dockerfile that identifies the dependencies for that image.
Tracing its history (and reflecting the accumulated clutter of my personal VM learning journey!) the draft TM351 VM is currently launched and provisioned using vagrant, partly because I can’t seem to start the IPython Notebook reliably from a startup script:-( Distributing the machine as a start/stoppable appliance (i.e. as an Open Virtualization Format/.ova package) might be more convenient, if we could guarantee that file sharing with host works as required (sharing against a specific folder on host) and any port collisions experienced by the provided services can be managed and worked around?
Port collisions are less of an issue for Sayler et al. because their model is that students will be working within the VM context – a “desktop as a local service” (or “platform as a local service” model); the TM351 VM model provides services that run within the VM, some of which are exposed via http to the host – more of a “software as a local service” model. In the cloud, software-as-a-service and desktop-as-a-service models are end-user delivery models, where users access services through a browser or lightweight desktop client, compared with “platform-as-a-service” offerings where applications can be developed and delivered within a managed development environment offering high level support services, or “infrastructure as a service” offerings, which provide access to base computing components (computational processing, storage, networking, etc.)
Note that what interests me particularly are delivery models that support all three of the following models: BYOD, campus lab, and cloud/remotely hosted offerings (as a crude shorthand, I use ‘cloud’ to mean environments that are responsive in terms of firing up servers to meet demand). The notions of personal computing environments, course computing environments and personal course computing environments might also be useful, (for example, a course computing environment might be a generic container populated with course software, a personal course computing container might then be a container linked to a student’s identity, with persisted state and linked storage, or a course container running on a students own device) alongside research computing environments and personal research computing environments.