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Language: Personalization
Expertise: Beginner
Apr 25, 1997



Building the Right Environment to Support AI, Machine Learning and Deep Learning

What's happening with multi-user 3D servers for VRML worlds?

What's happening with multi-user 3D servers for VRML worlds? Can I take my avatar into any world yet?

There are a few companies selling commercial versions of multi-user 3D servers, or community servers as they are often called. But it's not a healthy marketplace at the moment. In fact, Black Sun has just pulled out of the server market, and laid off its marketing team and all but one member of its sales staff. The company is going to focus on doing large projects for selected customers rather than trying to get revenue through sales of the server. Integrated Data Systems has also decided there's no money in multi-user servers at the moment. With an eye on the progress of multi-user standards, IDS is standing on the sidelines for now.

One of the first to market was Black Sun with its CyberHub Server. Renamed Community Server 2.0, it is oriented toward making multi-user worlds commercially successful by enabling advertising on banners and via robots, as well as by enhancing person-to-person communications with its free Passport multi-user client. Passport gives everyone with this 1.1MB client the ability to join multi-user communities based on Black Sun servers and to use a variety of VRML browsers as plug-ins to either Netscape Navigator or Microsoft Internet Explorer. You can even visit non-VRML worlds hosted on the server network as long as you have a Passport-compatible viewer to see them with.

Passport supports the use of either custom or off-the-shelf avatars in VRML 1.0 or 2.0 and has gesture buttons so avatars can be expressive. If you want to have voice chat, you need to use CoolTalk or NetMeeting software. The server and the client can be customized using APIs that can help with integration of the server with a database, and a corporate Web site.

Then came OnLive! with its OnLive! Community Server. OnLive! is going after the business user and stressing the voice communication aspect of its technologies. The server lets groups meet at any URL address and speak in real-time. The audio works with online text and graphics and in OnLive!'s non-VRML 3D chat spaces.

To persuade you to try it out, OnLive! is giving away a CD with a five-voice version of its server. For remote classrooms, conferences or customer support this seems a great technology. There are server solutions for both audio and 3D avatar based interactions.

OnLive! Traveler is the only 3D Virtual World browser software that allows groups of people to talk through expressive, animated avatars. Users are represented by 3D customizable avatars that "lip-synch" what that person is saying in real-time. If you don't want the avatar side of this, you can just use OnLive! Talker and have audio chat on any OnLive! enabled Web site, meaning one using OnLive!s server technology. See www.onlive.com/promo/wwa.html.

Multi-user can be a dangerous area for companies to explore. Worlds Inc.'s recent collapse into an 'on-the-market core' demonstrates that despite high demand for multi-user experiences, as evinced by the popularity of Alphaworld and Worlds Chat, there isn't sufficient demand yet for developer tools, servers and content to keep a company afloat. Or at least not without careful focus on one market segment.

Worlds' multi-user server software is now in the hands of a new company, Circle of Fire, who is selling it to those companies and individuals wanting to create new zones with Worlds Inc.'s ActiveWorlds technology. This is not VRML; it uses the RWX file format and can do things VRML can't manage yet like, streaming delivery of objects. ActiveWorlds have the distinction of letting users build for themselves within their spaces, play Java-based games and communicate with fully animated avatars. You can teleport around the worlds and make personal creations for visitors to see as permanent features of the world.

ActiveWorlds is compatible with both Netscape Navigator and Internet Explorer, and both update automatically when you visit the site, so you never have to worry about having an out-of-date browser or world. Server prices range from:

personal use at $69 plus a subscription of $23 per year for an area of 200x200 meters — which can cope with up to eight simultaneous users —


the smallest commercial space at $995 plus a subscription of $495 per year for an 800x800-meter space and support for up to 24 users.

After that, the sky is the limit. Servers are available for Sun Solaris, Win 95 and NT 4.0. See www.activeworlds.com for further details.

Sony is still in development with its Community Place Bureau multi-user server software. It's available as a free alpha download for Win 95 and NT from vs.spiw.com/vs/server/bureauPC.html.

As the only multi-user VRML server still in development, it's the one to watch. This server will allow you to share VRML 1.0 and 2.0 worlds using the Community Place VRML 2.0 browser. The server is restricted to support a maximum of 12 connections, but if you have a powerful workstation you can contact Sony about being allowed to host more visitors.

Sharing a world is simple — you need to add one line to an existing VRML1.0 or VRML2.0 world file, which will tell the Community Place browser where your world server can be found on the Net: WorldInfo { info [ "VsServer:hostID:port" ] }. You run the server on your PC and anybody loading the VRML 1.0 or 2.0 file into a Community Place browser will be automatically connected to the shared world. This means you can supply details of the world in an archive file or on CD, as well as dynamically on your server, and then have users visit the multi-user version on your server.

When connected, users can see avatar representations of other users, use text chat to talk to each other and express emotions with the avatar buttons. Community Place Bureau running on your PC allows you to share scenes, avatars, and behaviors including shared animation, games, and collaborative tools. All behaviors are programmed in Java.

ParaGraph has plans to enter the multi-user market in a small way by providing a limited-traffic personal server. This will be one of the add-on modules to go with ParaGraph's Internet Space Builder tool. Look for news of this later in the year on www.paragraph.com. A ParaGraph multi-user server facility has existed for a long time, but so far has only appeared at trade shows. There are also commercial multi-user worlds that ParaGraph has produced for the Japanese market, entry for members only and worlds made for IBM's Digital Library project, none of which are accessible on the Internet. Last December's bundling deal with SGI and Cosmo Player may presage some joint venture in the future.

Oz Virtual uses free distributed server technology to provide access to any VRML world in a multi-user mode. It's only possible to view and participate in Oz multi-user worlds themselves by using the Oz Virtual browser. The distributed server network uses load balancing for scalability and extensibility. There can be between 100 to 1,000 users per server depending on the performance requirements. (Oz Club claims to be able to cope with an unlimited number of visitors.) The Oz multi-user server runs on Win 95, NT and UNIX platforms.

To keep in touch across many large worlds, there's Oz Virtual Pager. This is a watchdog program that makes any Oz Virtual user pageable if someone is looking for them. Even if Oz Virtual isn't running, you will still get the message as long as you are online. And of course this means you can track down friends in any Oz world.

The addition of Voxware audio chat to its client and server means you can choose voice or text for conversations while listening to bands play live at special Oz-casts. The client software is compartmentalized, so the chat functions are separate from the 3D viewer. This means you can keep talking to a group of people while viewing a completely different site, which extends the use of the Oz server to group meetings in the same way as OnLive, although you have to use Oz sites as a 'lobby' to meet in.

Oz is looking to partnerships with ISPs to extend its server network. In addition to its client and server API, Oz is due to release an SDK of an Oz toolbox for game developers in April or May 97.

Then there's Integrated Data Systems with its VRealm 3D Media Server technology and multi-user VRML browser. The server provides multi-user capabilities within worlds whether or not the worlds themselves have multi-user support. All you need to do is use the VRealm multi-user browser 2.0. It comes in a stand-alone or plug-in form and can be used as a regular VRML 2.0 browser or, by right clicking and using the multi-user menu options, as a multi-user browser. To connect, you need to know the address of the server. If you're behind a firewall you'll need to know your proxy server and port information. Then you enter the URL of your avatar; a collection is provided with the browser download, or use your own VRML 1.0 creation. The 3D Media Server allows real-time audio (LiveAudio) and text chat as well as file sharing while in multi-user mode.

IDS has decided not to commercialize its multi-user server and browser technology at this stage, preferring to concentrate on its authoring software and other developments.

Tribe is Chaco's multimedia 3D multi-user MUD server, which runs on Windows/NT, Windows95 and UNIX platforms. It coordinates multi-user animation, voice and location information in real-time, and can accommodate up to 500 simultaneous users per server computer. You can scale Tribe to a larger numbers of users by distributing the load across multiple servers.

Tribe is especially suitable for use with Pueblo, Chaco's multimedia client application but can be used with other multiuser client applications as well. Download Pueblo from www.chaco.com/pueblo.

A good place to try out Tribe and Pueblo is the Simprov! site at www.metaplay.com, where you can join in improvised comedy while testing your avatar. Most MUD worlds are accessible only by telnet links; Pueblo can function as your 'telnet' client for Netscape, so that you can click on 'telnet://' links and connect to worlds.

Sense8 has a product called World Server, currently in developer's beta. It's target is the business user who wishes to share data. Sense8 plans to have its WorldUp world creation tool exporting VRML 2.0 before the end of the year, so thei World Server may become particularly useful to high-end VRML developers.

What's missing from all these multi-user experiences is the ability to see into one world from another and to move seamlessly from world to world. At the moment there is the need to click to change worlds using an address list, be it on a menu or in a teleport booth. If you're moving within one server system, you can at least keep the same avatar body but if you want to move to another format of world, the avatar standards movement hasn't caught up with you yet.

If you're on the Mac, you're still waiting for multi-user technology to reach you. Unfortunately, all of the above technologies are only available on Windows NT or UNIX servers or as Windows 95 or NT browsers. Black Sun says it will provide a version of Passport for the Mac; I suspect Black Sun is waiting for a Mac VRML 2.0 browser to come out — without one, there's not much point having Passport.

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