By Bertrand Reyna-Brainerd
It will come as news to few of you that the pace of advancement in computer technology has exceeded all expectations. In 2013, 83.8% of American households owned at least one personal computer.[1] In 1984, when the US census first began to gather data on computer ownership, that number was only 8.2%. At that time, a debate was raging about the scope of personal computing. Would every household need to own a computer, or would they remain a specialized tool for researchers and IT professionals? Even the mere existence of that debate seems inconceivable today, and yet the era of personal computing may already be drawing to a close. This is not due to a decline in the need for or utility of computing resources, but by the explosive growth of cloud computing. Amazon Web Services’ AppStream 2.0 is a significant step toward “cloudification,” and toward a future in which all forms of computation are increasingly delocalized.
Our laboratory, which labors under the title of “The Laboratory for Rational Decision Making,” applies a variety of approaches in its search for patterns in human behavior and the brain activity that underlies them. In 2016, David Garavito, a J.D./PhD graduate student at Cornell, Joe DeTello, a Cornell undergraduate, and Valerie Reyna, PhD, began a study on the effects of risk perception on sports-related concussions. Joe is a former high school athlete who has suffered a number of concussions himself during play, and is therefore able to provide personal, valuable insights into how these injuries occur and why they are so common.
The team has previously conducted research for this project by physically traveling to participating high schools and carrying a stack of preconfigured laptops. This is not an uncommon method of conducting research in the field, but it imposes several limitations (such as the cost of travel, the number of students that can be physically instructed in a room at one time, and by the number of laptops that can be purchased, carried, and maintained). What’s more, the type of information required for the research could be easily assessed online—they only needed to collect the typical sort of demographic data that has long been gathered using online polls, as well as measures such as memory accuracy and reaction time. Most of this legwork is performed by software that was designed to operate only in a physical, proctor-to-subject environment.
At that point – Joe and David came to me and asked if we could find a better solution.
I was not initially sure if this would be possible. In order for our data to be comparable with data gathered on one laptop at a time our applications would have to be reprogrammed from scratch to run on the web. However, I agreed to research the problem and consulted with the IT@Cornell Cloudification Team. Marty Sullivan, Cloud Engineer, helped us discover that Amazon Web Services (AWS) and Cornell were testing AWS’s then-unreleased product: AppStream 2.0. Amazon AppStream 2.0 is a fully-featured platform for streaming software, specifically desktop applications, through a web browser. The most attractive component is the fact that the end-users are not required to install any software – they can simply access the software via their preferred personal device.
The AppStream 2.0 environment has a number of advantages over a traditional remote desktop approach. When a user connects to our system they are presented with an option to choose an application. After selecting an application, only that application and its descendants are displayed to the user. This avoids several of the usual hassles with virtual computing, such as sandboxing users away from the full Windows desktop environment. Instead, the system is ready-to-go at launch and the only barriers to entry are access to a web browser and an activated URL.
Once the virtual environment has been prepared, and the necessary software has been installed and configured, the applications are packaged into an instance that can then be delivered live over the web, to any number of different devices. Mac, PC, tablets and any other device that has a web browser can be used to view and interact with your applications! This package resets to its original configuration periodically in a manner similar to how Deep Freeze operates in several of Cornell’s on-campus computer laboratories. While periodic resets would be inconvenient in other contexts, this system is ideal for scientific work as it ensures that the choices made by one participant do not influence the environment of the next.
It is difficult to overstate the potential of this kind of technology. Its advantages are significant and far-reaching:
- Scalability: Because Amazon’s virtual machine handles most of the application’s processing demands, the system can “stretch” to accommodate peak load periods in ways that a local system cannot. To put it another way, if a user can run the AppStream web application, they can run the software associated with it. This means that software that would otherwise be too large or too demanding to run on a phone, tablet, or Chromebook can now be accessed through AppStream 2.0.
- Ease of use: End-users do not have to install new software to connect. Applications that would normally require installing long dependency chains, compilation, or complicated configuration procedures can be prepared in advance and delivered to end users in their final, working state. AppStream 2.0 is more user friendly than traditional remote desktop approaches as well, all they need to do is follow a web link. It is not necessary to create separate accounts for each user, but there is a mechanism for doing so.
- Security: AppStream 2.0 can selectively determine what data to destroy or preserve between sessions. Because the virtual machine running our software is not directly accessible to users, this improves both security and ease of use (a rare pairing in information technology) over a traditional virtual approach.
- Cross-platform access: Because applications are streamed from a native Windows platform, compatibility layers (such as WINE), partition utilities (such as Apple’s BootCamp), or virtual desktop and emulation software (such as VirtualBox or VMWare) are not needed to access Windows software on a non-Windows machine. This also avoids the performance cost and compatibility issues involved in emulation. Another advantage is that development time can be reduced if an application is designed to be delivered through AppStream.
- Compartmentalized deployment: Packaging applications into virtual instances enforces consistency across environments, which aids in collaborative development. In effect, AppStream instances can perform the same function as Docker, Anaconda, and other portable environment tools, but with a lower technical barrier for entry.
Disadvantages:
- Latency: No matter how optimized an online system of delivery may be, streaming an application over the web will always impose additional latency over running the software locally. Software that depends on precise timing in order to operate, such as video games (or response time assessments in our case) may be negatively impacted. In our case, we have not experienced latency above a barely-perceptible 50 ms. Other users have reported delays of as much as 200ms, which is variable by region.
- Compatibility: Currently AppStream 2.0 only has Windows Server 2012 instances available, and access to hardware-accelerated graphics such as OpenGL is not supported. This is expected to change in time. In terms of the software itself, there are often additional configuration steps that are required to get a piece of software running within the Appstream environment compared to ordinary software install procedures.
- Cost: To use AppStream 2.0 you must pay a recurrent monthly fee based on use. This includes costs associated with bandwidth, processing, and storage space. You are likely to be presented with a bill on the order of tens to low hundreds of U.S. dollars per month, andyour costs will differ depending on use.
Ultimately, the impact of AppStream 2.0 will be determined by its adoption. The largest hurdle that the product will need to clear is its cost, but its potential is enormous. If Amazon leverages its position to purchase and deploy hardware at low rates, and passes these savings on to their customers, then it will be able to provide a better product at a lower price than the PC market. And if Amazon does not do this another corporation will, and an end will come to the era of personal computing as we have known it.
[1] U.S. Census Bureau. (2013). Computer and Internet Use in the United States: 2013. Retrieved March 29, 2017, from https://www.census.gov/history/pdf/2013computeruse.pdf.