Software Lets Conferees Share Screen
How many times have you huddled over someone else’s computer screen, collaborating on a project? But what if the computer screen you need to see is across town--or even across the country?
Now there’s “personal conference” software that allows two people on two computers connected by a telephone modem to collaborate interactively by revising or critiquing the same screen image.
This promises to be a fast-evolving family of products, so you can look forward soon to being able to share actual data files, not just images of them, or share a computer program or participate in a session with two others.
Among the competitors are Intel Corp. ((800) 538-3373), whose ProShare family of products ranges from a $99 entry-level program to a $2,499 package that includes live video. DataBeam Corp. ((800) 877-2325) has FarSite for Windows, available bundled with a trend-setting modem from AT&T; that can transmit voice and data simultaneously over a standard telephone line. Crosswise Corp. ((408) 459-9060) has Face to Face, a Mac-to-Mac product, with a Mac-to-Windows version scheduled for release in April.
What all of these programs have in common is that they allow two computer users to link screens via phone line and carry on a “discussion” about a document appearing on both screens. They “talk” by typing and using various graphics tools to highlight portions of the image in colors, or by drawing symbols or writing on the screens with their mice.
At the entry level of this category of software, the screen images are just “bit-mapped” copies of whatever documents each participant has chosen to prepare in advance of the electronic conference. It’s just as if you had printed the documents on paper and passed them out at a meeting for everyone to mark up.
When the meeting is over, you’ll have the marked-up image files in your computer, just as you would have marked-up pages. You’ll still have to make the agreed changes in the original files. But, unlike life with paper, each participant can quickly add images of new files to the on-line conference while it is underway.
Each of the programs has its own design metaphor to try to make its use more intuitive.
FarSite treats its screen images as if they were a series of slides to be projected. ProShare’s screen resembles a page in a spiral-bound notebook, with tabs on the side to let you easily choose which page to view. The Face to Face screen simply presents images in a “document window,” much as if you were viewing a printed page on the screen. This $295 program allows comments to be superimposed on the document image, like paper Post-It notes.
These programs require virtually no knowledge of the communications arcana (about protocols and parameters) that makes ordinary computer-to-computer modem connections so difficult. The downside is that both participants have to have the same program, although not necessarily the same kind of modem or even the same speed of modem.
Intel’s $99 ProShare has one advantage over the others: You can use it to connect to another computer that has modem software but not ProShare, and the program will up-load a receive-only copy of itself to the other computer. The user of that machine can then answer ProShare calls, but would have to buy a full version of the program to be able to call others.
FarSite is particularly useful because of the unique voice capability of the AT&T; modem available as a $549 modem-software bundle. (The software alone is $179.) When the program is operating in data-only mode, it can transmit at 14,400 bits a second.
If each user has a telephone connected to the modem, all one has to do is pick up the receiver during a FarSite session and the telephone at the other end will ring. The data speed falls to 4,800 bits a second while you’re talking, but jumps up automatically as soon as
The advantage is that with only a single phone line shared by computer and voice phone, you can simultaneously engage in an on-screen markup session and discuss the details with your collaborator. Of course, in offices where modems have their own telephone lines, you can use any of these products and talk over the voice line while communicating at full modem speed over the separate data line.
The high ground in computer conference products is held by Intel’s ProShare Video system, which is typically bought through the telephone company at huge discounts off its $2,499 list price.
The telephone company is going to make its money selling you an ultra-high-speed telephone line, called ISDN service, to accommodate the mass of data the Intel system transmits.
In addition, you will need a powerful computer, at least a 486 machine running at 33 megahertz, and with two empty slots inside to hold the two processor cards that come with the ProShare system.
You also get a small video camera housed in a squat case designed to sit on top of your monitor and capture your image as you work at the computer. A small combination earphone-microphone takes care of the audio.
Video conferencing is not as easy as voice, despite the clever design of the ProShare software. The video image, which can be an eighth as large as your screen or as small as a thumbnail, is broadcast at half the number of frames per second we see on broadcast television. Movement is jerky and resolution is quite grainy.
Despite the high band width available on the expensive ISDN phone line required for the system, the video signal is blanked out while data is being transmitted, such as when sending the next page in the spiral notebook.
But what is considerably more disconcerting is that the audio signal is lost as well.
On the other hand, you can send segments from a videotape or any other video signal over the system, and you can move the small Intel camera around to portray objects that aren’t in your computer files, such as photographs or product samples.
