Tridia’s Doublevision

If the name Doublevision sounds familiar, you’ve been around UNIX a while. There have been a host of products with this name, designed to allow UNIX and terminals to coexist a little easier. Tridia’s Doublevision is the same Doublevision, surprisingly still only at version 2.0. According to the Doublevision User’s Guide, this is "The next generation of the fantastically popular remote control software utility!". Fantastically popular seems a bit of hype, considering the lack of character terminals in most of today’s networks.

What does Doublevision do? The primary role of this UNIX utility is a control tool for watching and managing a remote terminal either through a direct connection, over a network, or through a modem. Doublevision was used in the early 90s to support a wide variety of terminals, many of which may not have had drivers for the SCO platform then in use. Automatic translation of terminal-to-terminal codes allowed sessions on one character terminal to be viewed on another with ease. Doublevision also includes the ability to talk to users over the network or direct connection, but that’s something UNIX has had almost from the start.

The main reason for using Doublevision is to watch what users are doing. We used it extensively in teaching environments where we could monitor each student’s activities and play them back on demand to isolate mistakes. Whoever is running the Doublevision software can cause user’s screens to go blank, which we used to prevent game playing during lessons. All these features existed in the first version, and while Tridia has improved them a little, the only real change to Doublevision is a new user interface with pull-down menus and a log capability for every keystroke. Other than that, this seems to be the same tool used ten years ago.

Installation of Doublevision is relatively easy but a knowledge of your system is required. Don’t expect to have an easy install if your system administration skills are raw. We downloaded the software for both UNIX and Windows NT systems from the Tridia Web site, along with User’s Guide and Installation Guide. The installation took about twenty minutes. The download version is good for thirty days unless you purchase a license. It’s a huge file (3.6MB) without documentation, so get a fast Internet connection.

Without wasting too much space in this magazine, it’s easy to summarize Doublevision’s audience. If you need to watch your users and every command or screen they use, Doublevision is handy. If you don’t teach users or have to troubleshoot them often, then Doublevision won’t do anything for you. Also, characters terminals and terminal emulators are rapidly disappearing in our environments, replaced by X terminals and Windows X clients. Sure you can watch a Telnet session from a Windows 95 machine, but do you need to? As a tool for a teacher or help desk with clients using character-based access only, Doublevision may be ideal. For all others, there’s no real reason to install the product. It’s nice to see this veteran piece of software again, but Tridia has a tough road to build a lot of new users.