Internet Groupware Technologies – Past, Present, and Future

Marek Podgorny, Krzysztof Walczak, Dave Warner, and Geoffrey C. Fox
Northeast Parallel Architectures Center, Syracuse University
111 College Pl., Syracuse, NY 13244
[podgorny, walczak, davew, gcf]@npac.syr.edu

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Abstract

The article discusses recent developments in Internet groupware, with special focus on synchronous collaboratory. Commercial systems are briefly presented, followed by a discussion of main research topics in the current groupware research programs. We discuss actual implementation of a synchronous groupware using as an example TANGO Interactive, a collaboratory designed and implemented in NPAC. The article is concluded by presentation of the concept of Intermental Computer, a model for the ultimate synchronous Internet Collaboratory.

1. Introduction

The Internet has been created a quarter of the century ago to enable, foster, and support cooperative work. The unique feature of the Internet endeavor was its completely distributed and open character, with no central agency controlling its technology or administration. The network has grown as a result of consensual cooperation between independent parties. The very process that the Internet was supposed to enable became also a foundation of its own existence, growth, and success. It is the assertion of this article that, after the unprecedented explosion of Internet popularity in the general population, the Internet technologies will breed a completely new way for people to interact via their desktop machines. This technology will soon affect all aspects of life of the technosocieties, including a profound change in business practices.

The "groupware" term is, to a large degree, synonymous with the CSCW term – Computer-Supported Collaborative Work. The term, as many other words in the computer-related lingo, is fuzzy. The fuzziness of terms in the technological arena is mostly caused by attempts of the marketing specialists from computer companies to invent new ways of describing essentially identical products and services. In the following, we will briefly discuss various meanings of the term "groupware" in the marketplace. We will start however with an attempt to define groupware from the analytical viewpoint. This definition will help us to establish a reference point to the following technical discussion of the emerging new technologies.

In our view, groupware is as much technology as it is a human process. The two are merged to create environment supporting collaborative work. There are three basic components of groupware: (1) knowledge base (technically, a data repository of any kind), (2) workflow (a set of rules describing the activity in which a group of people participates), and (3) collaboration (a process of exchanging messages between group members). All three components are intertwined in a groupware package. Workflow definition can be stored in the knowledge base, and messages created by the collaboration process may become part of the knowledge base. Workflow outlines the scope of the collaboration process, which can also be affected by the contents of the knowledge base.

The extent to which the three basic components are used in different situations varies. Let us consider an example from business environment: four typical business activities involve product development, marketing, sales process, and bookkeeping. In bookkeeping, the collaboration process is minimal. Two dominant factors are workflow and knowledge base. In marketing, workflow is hardly relevant, while knowledge base is extensively used in the collaboration process that has to result in new marketing strategies. In product development, collaboration and workflow dominate. The sales process is almost completely dominated by collaboration, with workflow being marginally important and knowledge base playing no role (please, note that salespeople rarely know anything – it is sufficient that they know everybody!).

In this article we will be mostly concerned with the collaboratory aspect of the groupware. This is certainly a non-standard approach. This focus is motivated by our belief that Internet will revolutionize this particular aspect. Two other groupware components are affected to a different degree. The knowledge base technology has been impacted in a tremendous way by "socialization" of the Internet. Vast corporate data repositories have been made available to the public. The implications of this fact for the business process are unclear. The lower operational costs of support and marketing efforts are definitely on the positive side and have been very quickly embraced by business community. The truly important data remains on the corporate servers hidden behind firewalls. The benefit of being able to include "external" data, previously not readily available, in the business decision process seems obviously beneficial, but the attempts to include such information in a structured fashion in the groupware packag are still immature. Internet did not significantly affect the dataflow process. In the future, we may see changes in business practices as ubiquitous, secure networking enables true virtual offices. The impact of this process is not evident yet. On the other hand, the vastly improved Web technologies enabled a new paradigm – synchronous collaboration.

 Traditionally, groupware supports asynchronous collaboration: the messages are being forwarded and stored in the knowledge base. They can be accessed and acted upon at any time. Without any doubt the most successful groupware application is electronic mail. The popularity of the asynchronous model stems from two sources. First, it is a very natural way of communication that vastly improves work efficiency. For certain types of communication e-mail is much more efficient than a phone call. Second, digital networks, until recently, were unable to support synchronous communication between people. After all, Internet phones still have a long way to go to match quality and reliability of a phone line. We note that this particular aspect of Internet technology is improving in a quite amazing pace, and that the synchronous collaboration is becoming an important communication channel for social, business, government, and defense activities. We define synchronous collaboration as a process of a computed-mediated excnge of information in which messages are being transmitted and presented to the users instantaneously. In this context we also need to mention that introduction of the term of "synchronous collaboration" rendered additional and different meaning to the notion of "asynchronous collaboration". The traditional meaning of this term has been extended to a process of asynchronous retrieval of the sessions of synchronous collaboration sessions (record and playback). This functionality is currently a subject of intense research.

The article is organized as follows: Section 2 provides a brief discussion of those commercial groupware products that include a synchronous component. In Section 3 we discuss general taxonomy of collaboratory applications and present advanced collaboratory functionality that is currently being researched and implemented in a number of academic projects. We also present one implementation of an advanced Internet collaboratory system: TANGO Interactive. Finally, in Section 4 we present a vision of ultimate collaboratory: Intermental Computer.

2. Commercial Systems – the Past

The most popular commercial groupware systems, such as Lotus Notes, IBM Office Vision, Microsoft Exchange, or Novell Groupwise, do not have synchronous components. Only recently some of those systems have been expanded to become Internet-aware. Lotus Domino server is an example of this trend.

 These systems are all useful and rather mature, but the limited volume of this article prevents from an in-depth analysis. The two most popular Internet collaboration systems are Netscape Communicator suite and Microsoft's NetMeeting. There is also a number of data conferencing tools from smaller companies, such as VocalTec's Internet Conference [http://www.vocaltec.com/], Centra'a Symposium [http://www.centra.com/], or Contigo's Itinerary [http://www.contigo.com/].

 VocalTec's product is a shared whiteboard which, cleverly using OLE technology, enables collaborative viewing of basic Microsoft Office document types (Excel, Word, PowerPoint). With added chat and point-to-point audio channel, Internet Conference (IC) is a pretty complete Internet data conferencing system. Unlike NetMeeting (see below), IC does not use shared display technology. IC does not explicitly use any Web technology – it is a distributed OLE application. The system is strictly proprietary and non-extensible.

Contigo's Itinerary is a Java applet allowing for group viewing of PowerPoint presentations. It is a single purpose tool suitable for "distributed seminars". In addition to the PowerPoint slides, Itinerary supports "shared browser" (group web surfing), a chat, a rudimentary session control, a telepointer, and file distribution. Documents can be transferred to all conference participants, and appropriate applications are automatically started to view the documents. No collaborative work on such distributed documents is possible. The product does not support audio – standard phone lines are used. Itinerary is a an example of a domain-specific collaborative Web system developed for a niche market. The system does not offer any extension capability. It does not have support for any form of asynchronous groupware or for structured contents repositories.

 Centra's Symposium is a distance learning system. Distance learning is one of the most important applications of synchronous collaboratory systems. Symposium is implemented in Java and executed from the browser. The system is narrowly specialized for distance learning and supports a rich menu of distance learning functions such as display of multiple document formats, including HTML pages and output from popular authoring systems, chat, one-to-many audio channel, and a set of tools allowing for feedback from the students regarding class pace and comprehension level. Students can also ask questions by raising the virtual hand and opening a public or private channel to the teacher. Teacher has access to some assessment tools such as multiple choice tests and quizzes that can applied on-line in real time. Symposium uses state-of-the-art Web communication technology. It comes with curricula authoring tools and document publishing interface. However, the system is specialized, non-extensible for 3rd parties, and does not support general groupware functionality.

The products from Netscape and Microsoft are markedly different. The large companies do not bother with niche, specialized tools. Instead, they offer general collaboratory frameworks. Netscape's Communicator is a set of Internet tools. In addition to the browser the suite supports Messenger for rich-text e-mail, encryption, and directory services; Collabra, a groupware server and associated front-end that support discussion forums with user-structured categories, user-configurable event notification, search tools and access control; and Conference, a synchronous, real time conferencing system that supports point-to-point audio, a whiteboard, a chat, a shared browser, and a file transfer utility. The tools are integrated on the level of usual windowing system integration, i.e. cut and paste. As an integrated collaboratory system, Communicator is a first step in unclear direction. There is no security, no global session and floor control (even within the Conference), no multiparty audio/video, no session recording (actually, there is not even a notion of a collaborative session). It is a little surprising since Netscape swallowed Insoft, the premiere synchronous collaboration tool company that had much more mature products (Communique!) on the market almost five years ago. The Conference audio tools internally uses Insoft's OpenDVE [http://www.mdlcorp.com/Insoft/products/OpenDVE/OpenDVE.html] architecture, which is capable of sophisticated session management. Netscape's definition of groupware seems to be "Internet groupware is what we sell". In reality, the current state of the Communicator is best described as a loosely coupled collection of well-known Internet communication tools with slightly improved interfaces given a coherent look-and-feel. With help of the Netscape server suite, the system can be successfully used to implement a modest Intranet application, but it is hardly competitive with products of the entrenched Intranet vendors such as IBM/Lotus Notes, ICL TeamWare, IBM Office Vision, or Oracle's InterOffice.

 For Microsoft, groupware is second in importance only to their operating systems. In the company lingo groupware is known as "advanced messaging". Microsoft solutions are completely proprietary and integrated with their BackOffice suite of servers. The asynchronous collaboration architectures of Microsoft products are too complex to be discussed in this paper. Their Internet Explorer comes however with a tool known as NetMeeting. Microsoft positions NetMeeting as their flagship electronic conferencing product. Current version of NetMeeting supports much the same functionality as Netscape's Conference: point-to-point unencrypted audio and video, multi-user whiteboard, text chat, file transfer, and directory service. These products use standard T.120 data conferencing protocol. NetMeeting most important feature is application-sharing capability. This is a general tool allowing sharing of arbitrary single-user application. The mechanism enabling this capability is display sharing. In Net Meeting, there is only e instance of each shared application running on one machine. All other participants see and can operate application display. We will discuss this technology in the next section. NetMeeting has no support for asynchronous groupware and the user can only participate in one conference. There is no support for conference recording, and no distributed shared browser. On the positive side, NetMeeting comes with an API allowing 3rd party developers to include its functionality in their applications. The system cannot be expanded this way, though. So, the Microsoft's notion of Internet groupware is "our code that is either part of Internet Explorer which is free, or part of the BackOffice which is not, and you need both for your Intranet".

3. Research Collaboratory Systems – the Present

3.1. Taxonomy of Synchronous Collaboratory Systems

Let us now take a more formal look at the general taxonomy of synchronous collaboratory systems. Current systems fall into two broad categories: shared display and even broadcast architectures.

  • Shared display systems have an architecture in which there is only one instance of the application running on a single machine. The conference agent replicates user input and application display on all workstations participating in the session. Shared display systems replicate entire functionality of the application used for collaboration. Examples of such systems include Microsoft's NetMeeting, Intel's ProShare, Sun's ShowMe, and Farallon's Timbuktu.
  •           From the functional point of view, the model is simplistic. There is no flexibility in shaping collaboratory process. Floor control is extremely awkward. There is no flexible session control, no support for security, and no support for asynchronous collaboration in any form.
  • Performance-wise, shared display systems are bandwidth-hungry and prone to failures. The entire display information must be passed to all collaborators. This is only partially helped by significant effort by some vendors to compress the transmitted data stream. Transmission errors lead to inconsistent state that can manifest itself in grotesque fashion. Generally, performance is unacceptable on slow connections. Use of this type of applications on mobile networks does not appear possible.
  • We also note that shared display applications are incompatible with Web paradigm, which assumes local intelligence on each web node.
  •           Event broadcasting systems only exchange state-changing events over the network. Each participating workstation runs a local copy of the application. This architecture can be further subdivided in two categories: virtual instance and independent data views architectures.
     "Virtual instance" is sometimes referred to as "collaboration transparency". Collaboration transparency allows application designed for a single individual to be used by a group of people without changing anything in the application. In this architecture, all events are shared. Such architecture is typically implemented by modifying the window toolkit so that the events are trapped before being sent to local applications and distributed to other session participants. Two examples of this architecture are Hewlett-Packard's Shared X and Old Dominion University project "Java Collaboration Toolset (JCE) [    http://www.cs.odu.edu/~kvande/Projects/Collaborator/ ], [http://snad.ncsl.nist.gov/~okim/jce/ ]. In the current incarnation, these systems share some of the drawbacks of shared display systems. Unlike for the former architecture, virtual instance architecture has a very interesting development path, which we will discuss below on the examples of DISCIPLE and T ANGO systems.
     "Independent data views" architecture adds flexibility of deciding which events are to be shared. Examples of such systems include

In the past, event-sharing systems were deemed impossible to implement. The Web architecture enables event-sharing applications I few important ways:

  • HTTP/Java/Javascript download mechanism ensures instantaneous distribution of software modules
  • Java Virtual Machine ensures identical, platform-independent environment for all applications
  • Modern object-oriented system design methodologies and standard object serialization mechanisms enable efficient state sharing and synchronization between distributed application instances, including support for the traditionally most difficult problems of accommodating latecomers and global synchronization.

3.2. Recent Research Thrusts

Interactive Collaboration and Visualization is one of the main research thrusts currently supported by US research agencies, including NSF and DARPA. It is very likely that the impact of this research will be comparable to the impact of DARPA sponsored research on packet protocols, which led to construction of the Internet. The list of current projects in this field can be found at http://ito.darpa.mil/research/icv/projlist.html. ICV research is also funded by other DoD and government agencies. In the following, we will first describe the general "hot" research issues in the field. We will illustrate these trends by discussing few selected projects. We will than turn to a more detailed description of our own project, code-named TANGO Interactive.

According to DARPA, the list of subjects of special interest for future collaboratory systems include the following research areas:

  • System accessibility via diverse portals, from hand-held through room-sized devices connected via any kind of network
  • System interoperability across diverse encoding formats, coordination and consistency protocols, and real-time services
  • System scalability: synchronous collaborations should be able to support ~10 active contributors, ~100 questioners, and ~1,000 observers
  • Reduction by an order of magnitude the time needed to generate collaborative applications
  • Enabling real-time discovery of relevant collaborators and information within task context
  • Reducing by an order of magnitude the time to establish collaborative sessions across heterogeneous environments
  • Reducing by an order of magnitude the time to review collaborative sessions
  • Improving task-based performance of collaborators by two orders of magnitude

The entire body of problems is expected to be tackled within four to five years. The few projects we present below make important initial steps towards future Internet groupware.

ISAAC (Integration of Synchronous And Asynchronous Collaboratories) is a project of University of Illinois and NCSA (http://www.ncsa.uiuc.edu/SDG/Projects/ISAAC) . The collaborative kernel of ISSAC is Habanero - a Java collaboratory framework developed by NCSA team. Habanero architecture is built around a central collaboratory server. Habanero is not strictly a Web system: it is implemented as a set of Java applications. Habanero supports, or will support in near future, certain critical functionality expected in an advanced collaboratory system, including session recording and playback, rich multimedia support, collaborative access to web databases, and a rich set of presentation and annotation tools for many data formats. Habanero is in many aspects very similar to TANGO system, which is discussed later. ISAAC projects also focuses on automatic indexing and synopsizing of collaboratory sessions.

MASH toolkit, a part of the UC Berkeley "Scalable Architecture" project (http://mash.cs.berkeley.edu) is a premiere Internet collaboratory framework. MASH builds on the foundation created by MBONE collaboratory tools. Multicast is a central ingredient of the MASH project around which entire architecture is built. This gives the system a very network-oriented slant and, while simplifying certain implementation issues, it complicates others, such as multiple sessions management, sessions access, and security. MASH contribution is however invaluable in such fields as quality of service and protocol support for collaboratory. We believe that MASH importance cannot be overestimated and that most of the project results will find its way into collaboratory systems built around different architectures.

Another very interesting Internet collaboratory project is Rutgers' DISCIPLE (http://www.caip.ruther.edu/multimedia/groupware). DISCIPLE is more a framework for development of collaboratory applications than a system. There seem to be only few publicly available applications. However, DISCIPLEs strength lies in the concept of using newest Java event delegation model to provide linkage between collaboratory applications and distributed collaboratory server, known as "collaboration bus". DISCIPLE is able to support collaboration transparency. Applications, implemented as JavaBeans, are able connect automatically to the system, without being modified from their stand-alone version. This implementation of collaborative transparency is however different than the implementations proposed earlier. As we mentioned, in the most trivial form collaboration transparency is supported by shared display systems and by "virtual instance" systems. This solution is in so much inflexible that the developers cannot decide which functionality should be shared. The Java SDK 1.1 event delegation model, used in conjunction with JavaBeans applications, aows for automatic implementation of both collaboration-unaware and collaboration-aware applications. In simplest case, DISCIPLE is able to take a JavaBean application module and automatically connect it to the collaboration bus by extraction of the GUI method information and automatic installation of event traps. This approach leads to a collaboratory transparent, event sharing application. However, the designer of a collaboratory module may decide to expose certain higher level events to DISCIPLES compiler, creating a collaboration-aware module that is then automatically connected to the collaboration bus.

 3.3. TANGO Interactive Collaboratory

TANGO Interactive is a synchronous collaboratory system. Its development has been sponsored by DARPA in the project "Collaboratory Interaction and Visualization" managed by Rome Laboratory. TANGO Interactive is very tightly integrated with Web infrastructure, with main system modules executing as within the browser. The system effectively turns web browser into communication device.

We have designed and implemented the system starting from the following few guiding principles that reflect our understanding of collaboratory concepts:

 - We do not really know how to build an efficient collaboratory. Since no truly successful collaboratory system exists, there is no blueprint for success. We have to therefore allow for an extensible system with very few limitations. TANGO must not define application specific protocols, application programming language, or limit in whatever way functionality of collaboratory applications.

 - The essence of the collaboratory function must be defined by application and by application only. It is up to application developer to specify requested collaboratory functionality for every application. This functionality may be obvious, as for a chat or audio conferencing, or highly non-trivial, as for a collaborative weather prediction and analysis application with a real-time computational backend. TANGO supports collaborative process for either type of application.

 - The most likely collaboratory applications are the applications supporting professional work in the stand-alone mode. This implies a necessity for a simple API enabling fast and easy porting process of the existing applications into the collaborative framework. TANGO supports such an API for applications written in few languages.

 Before we turn to the deeper description of the TANGO system, it is important to discuss its basic functionality. We perceive TANGO as a modest prototype of an open, extensible system that provides a technological framework for building subsequent generations of collaborative systems. It is therefore useful to make a distinction between the functional model and actual implementation. We tried to build a functional model that addresses and embraces a number of unresolved issues listed in Section 3.2. We hope that this model is sufficiently generic to serve as a framework for ongoing implementation process. Implementation methodology is often a compromise dictated by the current state of the art of the basic Web technology we are building upon: web browsers and the Java Virtual Machine. This state of the art is often a state of misery, as it should be expected from an infant technology. However, true to our belief that an efficient collaboratory can only be built by the arduous process of getting feedback from the users, we decided to provide a working implementation of the system regardless of the evolving technology.

 The functionality of the system directly addresses several of the following issues, vital to the further development of collaboratory systems:

  • TANGO is aimed at creation of shareable information spaces : The basic paradigm of many traditional collaboratory systems is to connect identical instances of few applications and allow them to exchange data objects or streams. We consider this paradigm way too restrictive. There is no basic reason to restrict collaborating people and teams to look at the same information in the same way or using the same tools. Collaboratory system should support coordinated but independent views of related information. Different presentation of information may be needed for various reasons: a 2D GIS display on the command and control main screen may be sufficient while the mission planner may want to see a much higher resolution 3D representation of the same information. In other cases, different information views may be displayed on workstation with different performance or graphics capabilities. In T ANGO , we allow different applications to exchange messages and act accordingly. The applications exchanging information can reside on either the same node or on different machines. This is an important feature, since, independently of supporting many richer collaboration models, it allows us to build complex applications from small, reusable modules. Consider, as a simple example, a tandem of a chat and a web browser. This tandem is replicated on multiple nodes. As the users chat, they may pass information about interesting URLs in the chat window. In T ANGO system, this information will be automatically recognized and passed to the set of browsers working in the collaborative mode. Another example is a simulation system created from a customized T ANGO environment: a simulation engine sends messages to both local and remote applications of various kinds, creating a war game or a crisis management center training module. In both cases, the users of the system have full access to the enormous information resources of the entire Web. This information may be presented to them either via a standard, familiar web browser interface, or via a set of specialized filters that tailor information display to a specific task.
  • Asynchronous collaboration is supported via database back-end : Session record and playback capability has been designed into the system as its fundamental component. This capability applies to both events and data streams and can be used review collaborative sessions in asynchronous fashion. Playback/review capability is provided also for real-time continuous data streams such as audio and video.
  • TANGO provides support for all synchronous collaboratory functions : Built in a stateless Web environment, TANGO is a statefull system. Basic design supports all functions of a synchronous collaboratory system, including session management, data/event distribution, flexible floor control, and multiple, configurable security levels. The system does not impose any restrictions on a number of concurrent sessions, users, or collaborative applications.
  • TANGO is very tightly integrated with the Web : This statement applies both to TANGO as a functional model and to its implementation. In the functional sense, tight integration with Web implies access to the entire informational potential of the Web. This is critical for the construction of the shareable information space discussed above. Further, designing TANGO functionality we have opted for the self-distributing software model for collaboratory applications. While this decision created a number of difficult software implementation issues, it also makes the system very easy to install, use, and extend. T ANGO is the first collaboratory system tapping full potential of applet download capability provided by Java.
  • Distributed visualization and manipulation of multimedia information streams : T ANGO provides scaleable multimedia support. Recognizing different performance requirements of continuous multimedia streams, TANGO provides mechanisms for decentralized distribution of such streams under TANGO session control.
  • Language independence : While almost entire T ANGO runtime and most of the applications are written in Java, there is no restriction on the language used to implement collaborative applications compatible with T ANGO . This design decision appears to violate the aforementioned requirement of application downloadability. Actually, methodologies for automatic distribution of applications written in languages other than Java exist and we are incorporating them into our implementation. We have decided however that, at least at present, restricting ourselves to Java would prevent us from extending our systems to such important domains as 3D visualization, high quality video streaming, and videoconferencing (especially multimedia encoding). In addition, T ANGO provides a truly unique support for applications written in JavaScript. Our ability to do so stems from the earlier decision of very tight integration of T ANGO with the Web.
  • Extensibility : As stated above, we firmly believe that ultimate success or failure of a collaboratory system depends on its application set. Video, audio, and whiteboard conferencing are just a seed of a collaboratory. Domain specific applications must be either implemented from scratch or ported from their stand-alone versions for a collaboratory to become truly useful. For this reason, T ANGO APIs for Java, C/C++ and Javascript have been written and well documented.

 Figure 1: TANGO Architecture

Figure 1 shows a simplified diagram of the system architecture. More detailed presentation of technical details can be found in [1] and [2], as well a on the project web site at http://trurl.npac.syr.edu/tango. The system differs markedly form any other web collaboratory system currently available. TANGO supports sophisticated inter-applet communication mechanism as well as communication between applets, interactive Javascript pages, and external application. Applications can be created and destroyed dynamically. TANGO collaboratory server does not have to be collocated with any of the HTTP servers from which applets are downloaded. The system is entirely distributed, and there is no restriction on system topology. All users can download applets from one http server or every user can get them from different server. This applies even to different instances of the same applet. The system also supports complete spectru of possible software distribution patterns, depending on the performance characteristics of the underlying network. On fast networks, all applets can downloaded from the server, on slow networks software can be distributed using push channels, ensuring that there is always a local copy of the newest version of each application available for quick startup. The server supports a set of sophisticated mechanisms ensuring application state synchronization and distribution, entirely under control of the application developer. There are no restrictions on the application protocol. In fact, TANGO supports a broad variety of collaboratory modules, from simple line and 2D chat rooms, via fully integrated multi-platform, multi-party audio-video conferencing, shared Web browser in which every link click is shared , layered, true multi-user whiteboards, collaborative search engines and database browsers, synchronized audio and video players, shared viewers of popular presentation formats, multi-user games, including 3D network games, to such advanced tools as scientific simulation packages used in science classes, and a complete set of tools for implementation of military and civilian command and control games and exercises. TANGO also seamlessly integrates application sharing agent of Microsoft's NetMeeting, allowing for concurrent operation of the display and event sharing collaboratory paradigm on one machine. The system has been designed for scalability. This goal is achieved by a unique architecture that makes a strict distinction between data and event distribution. No static data are sent through collaboratory server – the system uses download from distributed array of http servers for this purpose. All multimedia real-time streams are distributed over separate channels using multicast technology.

The system is currently being used in real-life applications. One of such special applications is distance learning subsystem of TANGO. The subsystem consists of the authoring, universal synchronous and asynchronous delivery package codenamed WebWisdom, audio/video tool, shared browser, and a set of tools supporting real-time interaction with students. The package is being used to deliver fully accredited classes from Syracuse University to colleges in Jackson, Mississippi; Baltimore, Maryland; and Atlanta, Georgia. It is also used for training and collaboration by a number of DoD agencies and supercomputing centers.

4. Intermental UltraScale Computer – the Future

The research systems described in the previous section are expected to evolve in incremental fashion for three to five years before they will move into commercial mainstream. Obviously, a completion of one research track does not imply end of the quest for better use of digital technology as the human-human communication medium. The upward path leads through the sparsely charted area of aggregating humans and computers via multimodal interfaces to form a kind of collective consciousness. Such research has already begun.

 New computers, communication and peripheral devices from biological, quantum, superconducting and other technologies promise UltraScale computing. One of the most obvious but still interesting biological computers is that represented by Nature's premier computer - the Human mind. There is the potential world (and space) wide linkage of billions of such human minds with large numbers of constructed devices (traditional computers) which form an Intermental network. We do not envisage this as a glorified next generation World Wide Web as this implies that each client (human mind) links essentially independently to a single server in a given transaction. The World's Wisdom is obtained by the incoherent sum of individual contributions. Rather as in a parallel computer, our Intermental computer will link entities coherently and synchronously together to tackle a single problem. Further, as described below, our concept is a major extension of the interesting and still developing shared immersive virtual environment In the latter, one represents the world classically by the actions of other people on it. In contrast, an Intermental net directly represents other participants through a rendering of their perceptual state.

An Intermental network reverses the traditional role of the human as the user of the computer system. Rather than the human as the usually asynchronous viewer of the computer's possibly parallel computations, we consider the conventional computer network as an aid to the parallel synchronous interactive Intermental network of linked minds. In another reversal, we are not trying to modulate an individual's perceptual state by an accurate representation of the physical world; rather our main aim is more effective modulation of the physical environment through an accurate synthesis of the perceptual state of the linked minds.

 We use the term "mind" to mean "consciously experienced perceptual state-space". Thus the concept of "linked minds" of the Intermental network refers to the capability of the network to modulate a coherent (phase consistent) co-perceptualization across an number of individual "minds" for the purpose of synthesizing a collective intelligence which will influence future iterations of a computational process. This Intermental linkage will allow the individual users to perceive the collective response dynamics of other minds while these minds reach states based on the knowledge of actions of the whole. Our multi-modal perception and expression systems (wearable computers), which are critical part of the concept, are designed to enhance and optimize the inevitably imperfect representation of each mind's state as it is transmitted through digital filters and networks and seen by others in the Intermental net. This leads to each mind having additional perceptual dimensions corresponding to either the state of indivual minds or the Intermental net's synthesis of a group perceptual state. This gives rise to a form of quasi-self awareness, where the computational properties of individual units are influenced by the state of the whole system. We believe that this experience of co-perceptual processes will lead to the emergence of new computational capacity not currently possible with current asynchronous networks linking incoherent (sequential) minds.

This Intermental network extends the familiar concept of a shared virtual environment where users respond to a changing system without direct knowledge of the thought processes (perceptual states) of other users. Rather than perceiving the other participants' perceptual states indirectly through their action on the physical environment, an Intermental network provides to each user direct awareness of the probable perceptual states of the other players at any moment.

We realize that the concept of Intermental computer will appear far-fetched to many readers. To make the idea more digestible, let us consider three application areas of such a device. The three application are: (1) special operations environments, (2) battlefield medical intelligence, and (3) crisis management. Intermental nets have two types of application impact; tactical and strategic and each of the chosen areas can be impacted in both ways. Tactically, the Intermental net can enhance split second decisions by providing an instantaneous awareness of the group perceptual state. Integrating this over time, members of the Intermental net are continually aware of the evolving perceptual state of others addressing the same problem and this can lead to better strategic decisions.

Special operations environments present a highly challenging situational scenario to the project of gathering, processing and depicting time-critical information. Present age operations are especially harrowing to military personnel due to the insidiously stealth nature of modern threats. Presenting critical information to key personnel who are simultaneously enabled/empowered to respond effectively has long been a problem. Inadequate capacity to cope with various threats necessitates great resource and personnel allocation just to insure that the higher level priorities can go forward. The concept of Intermental Computer responds proactively to this aim by specifying an "interventional informatics" methodology for comprehensively addressing the problem of connecting strategic personnel to emerging information and enabling their interaction with that information. We are currently developing a single, multimodally integrated interface system for the perceptibility and expressibility [5] of massive quantities of critical information for the DARPA distributed robotics project. Intermental Computer concept extends the focus beyond the issues of interfacing individual personnel by addressing issues of allowing the Intermental network control the robots.

Another example application is the battlefield medical intelligence [3, 4] where the traditional concept of telemedicine is augmented by an intelligent integrative system with distributed doctors and patients linked together coherently. Traditional telemedicine has proved inadequate in many circumstances and the proposed Intermental system appears to offer a more promising approach to quality time-critical health care.

 The final example is crisis management, which is quite similar to command and control and involves decision (judgment) support, which intrinsically mixes people and computers in real-time simultaneous interactions. TANGO Interactive collaboratory was originally developed to demonstrate the value of commodity (web) technologies in cost effective high quality command and control applications.

 In general, these applications lead to important requirements for the Intermental network which can be applied to a wide range of mission critical applications where the access to the intelligence of a collective of co-aware minds is essential to the optimal performance of the mission.

 The Intermental Computer prototype is being implemented using two key technologies: human-computer interfaces (HCI), collaborative systems, and parallel/distributed computing

The Intermental HCI. technology focuses on maximizing sensory throughput and expressional capacity of the individuals linked to this Intermental network. This component leverages the DARPA Bot-Masters project [http://www.pulsar.org/fallweb/papers/botmasters.html] that is developing an advanced body-worn HCI aimed at controlling behavior of an array of distributed robots. This system uses novel hardware interfaces and software built on extension of NPAC's NeatTools system [http://s008.infomall.org/ej/work.html , http://s008.infomall.org/ej/Thesis Proposal-03.htm]. NeatTools is a system developed to be adaptable to both the physiological and cognitive restraints of individual users and unique applications.

Naturally, linking an individual to so much real-time information requires both optimizing the amount and the level of understanding (quality of information) in the transferred data. We are building all our software systems on top of commodity web technologies for, as we have argued, [http://www.npac.syr.edu/users/gcf/HPcc/HPcc.html], this leverages the best available distributed information processing software.

A key Web based subsystem and our second major building block is the collaboration capability that will support the synchronous sharing of information (in the form of distributed objects) between the participants in the Intermental network. Here we build on the TANGO Interactive, a system described earlier in this paper. As mentioned above, Tango was originally built as a proof of concept that pervasive Web technologies could be used in Command and Control and now is part of the XII crisis management project led by Lois McCoy of the National Institute for Urban Search and Rescue. For the Intermental Computer project we are developing for TANGO the necessary new data fusion filters to aggregate data to form the higher level information processed by the HCI.

References

[1] L. Beca, G. Cheng, G. C. Fox, T. Jurga, K. Olszewski, M. Podgorny, P. Sokolowski, and K. Walczak, "Web Technologies for Collaborative Visualization and Simulation" in Proceedings of the 8th SIAM Conference on Parallel Processing for Scientific Computing, March 16-19 1997, Minneapolis, MN, http://trurl.npac.syr.edu/tango/papers.html .

[2] G. Cheng, G. C. Fox, T. Jurga, K. Olszewski, M. Podgorny, P. Sokolowski, and K. Walczak, "Java Enabling Collaborative Education HealthCare and Computing", Concurrency Practice and Experience, vol. 9, pp. 521-534 (97), http://trurl.npac.syr.edu/tango/papers.html .

[3] Warner D, Rusovick R, Balch D (1998) The Globalization of Interventional Informatics Through Internet Mediated Distributed Medical Intelligence, New Medicine (in press), http://s008.infomall.org/newmed/globalmed.html.

 [4] Warner D, Tichenor J.M, Balch D.C. (1996) Telemedicine and Distributed Medical Intelligence, Telemedicine Journal 2: 295-301.

[5] Warner, D., Anderson, T., and Johanson, J. (1994). Bio-Cybernetics: A Biologically Responsive Interactive Interface, in Medicine Meets Virtual Reality II: Interactive Technology & Healthcare: Visionary Applications for Simulation Visualization Robotics. (pp. 237-241). San Diego, CA, USA: Aligned Management Associates.