About the Multi-User Version of Transana

Transana-MU, the multi-user version of Transana, is designed to facilitate collaborative analysis. This page provides some basic information about the multi-user version, and how it differs from the single-user version of Transana. You can use this information to decide whether or not you need the multi-user version, or to learn more in general about the multi-user version.

If you already know that you want to use Transana-MU, you can go directly to the Transana-MU setup instructions for version 2.20 and later. That page provides a more detailed discussion of how to set up your computer and network for the multi-user version, and how to get it up and running.

Introduction to the Multi-User Version

Transana has three central components: the application program itself, any video or audio files that you are analyzing, and a database that contains your analysis--your transcipts, your clips, your keywords, and your collections.

The single-user version of Transana is designed for projects where all the video analysis is conducted on a single computer. It's self-contained--the data (video or audio files), the application (Transana program files) and the resulting analysis (the Transana database) are all located on the same computer. Only one person at a time can work on it.

In contrast, the multi-user version of Transana can split up these components. It allows users on different computers (and in different physical locations) to make changes to the same analysis files (the Transana database). Transana-MU is ideally suited for projects where several researchers are participating in collaborative analysis.

The key to knowing whether you need Transana-MU is this: do you need to share only video/audio data, or do you need to collaborate on analytic data also? If you only want to share video or audio data, and don't need to share access to the Transana database, then you don't need Transana-MU. You can share video and audio files by making sure that all researchers have local copies of them; because these files don't change there is no barrier to everyone having his or her own copy.

If the people who are collaborating want to be able to keep their data in the same Transana database, they should use Transana-MU. In this way, they can view collections and clips, and make changes to the database (for example, updating keywords, or a transcript) at the same time that someone else is doing this, even if that person is at a different location.

A second use for the multi-user version of Transana is for researchers who want to access their analysis from multiple computers, say offices in two departments or from work and home. To do this with the single-user version of Transana, you must carry your computer with you, while the multi-user version gives you the ability to connect to the same data from different computers.

About Sharing Video

When you want to share video data, each distinct location (i.e. each separate computer network) needs a copy of each video. This is because video files are large, and access times for video over the Internet are slow. An hour of video in the most compressed usable format takes about 650MB of disk space. Note that that comes down to over 10MB of data per minute of video, and that's if you use the most compact supported format. The Internet is just not fast enough to transfer data around the country at that rate. In addition, for video analysis purposes, you need the video to be really responsive. Internet traffic-related delays would be frustrating, and most streaming video formats don't provide the capacity to select an arbitrary location in a video file the way Transana requires. This problem is solved by each location having a set of the video files.

To help solve problems related to distributing video to each location, Transana can make use of the Storage Resource Broker (SRB). The SRB is a server that facilitates secure, encrypted transfer of video between locations. In addition, if you have a lot of video, the SRB can ease storage problems. With a centralized repository with ALL the video, various locations can then decide what videos they want to keep a local copy of, and they can pull down videos as needed, so that each location doesn't need enough storage to have the whole collection all the time.

About Sharing Analytic Data in Transana-MU

Sharing the Transana-generated analytic data is a separate process from sharing video data. Transana uses a database to store and organize all analytic data. In the multi-user version, you need a separate piece of software, a database server called MySQL, to handle the job of making the shared analytic data available to everyone in the project. When multiple people are accessing the same data set, a single MySQL Server manages all of the data requests in the centralized data repository. Unlike the video, copies of which are located at each local site, there is only one copy of the Transana database, which is located on a server at one location.

Keep in mind also that when you have multiple people all accessing the same data, you need a way for all of the different people to keep their data synchronized. If one person makes a change to the common database, everyone else needs to be able to see that change. Another component, the Transana Message Server can communicate between all the different copies of Transana-MU that are running at once in order to keep each copy up to date with the changes made by other users. It's all done behind the scenes, but it's an important function. (The Transana Message Server is little more than a customized Chat server like the one that works for AOL Instant Messenger.)

A Summary for Those Who Want to Use Transana-MU

Each person on your project needs a copy of Transana-MU. All of these copies connect to one MySQL server, which is where the analytic data (the Transana database) is centralized. They all also connect to a single instance of the Transana Message Server, which enables communication among the Transana-MU copies so that the data stays synchronized and everyone can see what everyone else is doing in real time, automatically.

The raw video (or audio) files are distributed so that each location has a copy, which is a compromise between storage demands and bandwidth issues; the raw video distribution can be handled using the SRB (or through the distribution of DVDs). Please note that research video with Human Subjects Data restrictions should not be sent over the Internet through e-mail or via FTP without the sort of file encryption that the SRB provides.

The MySQL Server, the Transana Message Server, and the SRB all work in conjunction with Transana-MU to allow complex collaboration that is not possible without all of these pieces.

The bottom line, though, is that only a couple of technical people in the project really need to understand all of this. The project needs one or two people to set up and maintain the MySQL Server, the Transana Message Server, and the SRB Repository, and to troubleshoot when the project runs into a server problem. Most car drivers can't explain the workings of the internal combustion engine or a transmission, but they don't need to be able to in order to drive to the store. We're in that same territory here. For example, most members of your project won't even know there is such a thing as a Transana Message Server, other than that they have to specify one the first time they use Transana in order to be able to connect to the data. After that first time, they'll forget it even exists.