Experiences with Using TANGO Interactive in a Distributed Workshop

Troy Baer, David Ennis, Jim Giuliani, and Leslie Southern
Ohio Supercomputer Center
1224 Kinnear Road
Columbus, Ohio 43212

David E. Bernholdt and Marek Podgorny
Northeast Parallel Architectures Center
Syracuse University
111 College Place
Syracuse, NY 13244-4100

Abstract


Together, the Ohio Supercomputer Center (OSC) and the Northeast Parallel Applications Center (NPAC) at Syracuse University delivered high-performance computing (HPC) training courses to a geographically distributed Department of Defense (DoD) user community.  In September of 1998, the Ohio Supercomputer Center (OSC) delivered a one day offering on the Fortran 90 programming language from the CEWES MSRC in Vicksburg, Mississippi. In January of 1999, the OSC delivered a two-day offering on OpenMP from the CEWES MSRC.  The TANGO Interactive collaborative software was used to deliver these courses simultaneously to participants at DoD Modernization Major Shared Resource Centers and Distributed Centers.  This report describes these prototype distance HPC courses, our experiences, and provides instructor and student guidelines.

Table of Contents

  1. Introduction and Background
  2. Course Materials
    1. Fortran 90
    2. Parallel Programming on the Origin 2000 Using OpenMP
  3. TANGO Interactive
  4. Classroom and Network Configuration
    1. Preparation and Support
  5. Problems Encountered
  6. Student Reactions
  7. Instructor Reactions
  8. Conclusions
    1. Lessons Learned
    2. Recommendations
  9. Future Directions
  10. Acknowledgements
  11. Figures
    1. Figure 1: TANGO Startup Windows
    2. Figure 2: TANGO Login Screen
    3. Figure 3: TANGO Control Application
    4. Figure 4: TANGO Chat Client
    5. Figure 5: TANGO Object Whiteboard
    6. Figure 6: DREN Connectivity Map
  12. Appendices
    1. Guidelines for Distance Training with Tango Interactive

Introduction and Background

One of the important missions of the DoD HPC Modernization Programming Environment and Training (PET) program is to provide user training to assist with the transition to scalable parallel computers and related leading-edge technologies.  However the fact that the Modernization Program's user community is distributed over such a large geographical area relative to the four Major Shared Resource Centers at which the PET program is based poses a real challenge to the development of a training program that is both effective and convenient for users and instructors.  "Distance learning" is one obvious response to this challenge. This paper describes a project aimed at transferring the tools and experience gained from a successful academic distance education effort into the more compressed, and in some ways more demanding environment of short-duration trainings, as traditionally used in the PET program.
Since the fall of 1997, the Northeast Parallel Architectures Center (NPAC) at Syracuse University has been working with the Computer Science Department at Jackson State University (JSU) to deliver semester-long academic credit courses to JSU students over the Internet, using the TANGO Interactive collaborative framework, developed at NPAC.  This work, which has been described in more detail elsewhere [cite previous preprint/SC98 paper] has been quite successful at several different levels.  It has been used to successfully deliver four classes (as of Spring 1999) covering material in large part unavailable locally to the participating students.  At a more fundamental level, it has served as an excellent venue to explore the social dynamics of distance education -- teaching styles, student and instructor interaction with the delivery tools -- and the technical demands.  In addition to new and improved tools to facilitate distance learning, the distance education effort has also driven significant improvements in the stability and robustness of the core TANGO Interactive system.  By the fall of 1998, we judged that TANGO, and our distance education experience, had reached a sufficient level that it made sense to begin the staged transfer of this technology into the PET training program.
The training environment differs from a regular academic environment in several important ways.  Most importantly, the timescale is significantly compressed -- trainings typically run one to three consecutive days six to eight hours a day rather than two to three days a week (typically three hours) for twelve or more weeks.  This means that technical problems with the delivery tools or the network can be much more disruptive in a training, placing a greater demand on the tools and the support staff.  Connected to this is the fact that attendees who experience technical problems with the class are less likely to return for another class using the same type of delivery.  In the interest of having things run as smoothly as possible, we made the conscious decision that in this early stage we should deliver trainings only to training rooms with support staff with some knowledge of TANGO present locally.  The ultimate goal of "direct to the desktop" delivery to individual researchers was deferred to future stages of the distance training deployment.
Also important to the use of TANGO in training was the fact that so far, the instructors for all of the distance education work to date had been NPAC staff who were thoroughly familiar with TANGO.  In practical use in training, however, a great many different instructors, perhaps with little or no prior experience in distance learning, would have to develop and adapt courseware to this new medium and deliver it.  It was primarily for this reason that the Ohio Supercomputer Center (OSC) was involved in this project. OSC has over ten years experience with high-performance computing, and as such, continues to build a repitoire of quality training offerings for the high-performance computing user.  At the beginning of this project, one of the two OSC instructors involved attended a two-day training on the installation, operation, and support of TANGO, while the other had no formal training with TANGO at all.
In the course of this project, two distance trainings were delivered.  The first, in September 1998 was a one-day, lecture-only class on a topic familiar to the instructor, Fortran90.  The second, presented in January 1999 was a two-day class on OpenMP on the SGI Origin2000, which included a hands-on laboratory component and was newly developed, so that the instructor had not taught it before either in normal or distance fashion.  The first class was also more conservative in that the number of remote sites was intentionally limited to two -- the ARL MSRC and OSC's training room -- while the second class was offered to all four MSRC training rooms, as well as to the Naval Research Lab in DC, and OSC.  Both of these trainings were successful in delivering the class to a geographically distributed audience located at multiple sites. At a more fundamental level, they were also successful as a framework in which to examine the issues around a more routine use of TANGO Interactive for the delivery of remote trainings.  The remainder of this paper describes in more detail the trainings conducted in this project, critically assess the results, and discusses prospects for expanded use if interactive distance training in the PET program.

Course Material

Fortran90

The first training class, presented in September 1998, was on the Fortran 90 programming language. In particular, the course is designed to present to users familiar with the Fortran 77 language standard the new features available in the Fortran 90 standard, such as dynamic memory allocation, derived data types, modules, and array syntax. The course has been taught several times by instructors at OSC, typically in an intensive one-day lecture format.

The notes used in this Fortran 90 course were originally written using Frame Maker by Dr. Dave Ennis of OSC. They were then converted to HTML by Victoria Sauber and placed on OSC's technical information server, and in this case they were presented by Dr. Troy Baer. These notes are split into sections dealing with specific Fortran 90 topics:

  1. Preliminaries
  2. Source, Types, and Control Structures
  3. Procedures and Modules
  4. Array Processing
  5. Pointers
  6. New I/O Features
  7. Intrinsic Functions
The course is taught as a series of lectures on the topics listed above. In "local" presentations, the notes usually are projected on a screen at the front of the classroom, using either an overhead projector and transparencies made from the Frame Maker source, or a projector attached to an instructor computer station which runs a Web browser to display the HTML version of the notes.  The TANGO-based delivery used a shared web broswer to present the HTML notes, and as is normally done in OSC's local presentations of the class, attendees are given the option of following along using either a hard copy of the notes or the online HTML notes using a Web browser on the classroom workstations.

Parallel Programming on the Origin 2000 Using OpenMP

In January 1999, the second training entitled Parallel Programming on the Origin2000 Using OpenMP was presented. This course targets the experienced programmer who is interested in the Origin 2000 architecture and the OpenMP application program interface (API).  OpenMP is a portable, scalable model that gives shared-memory parallel programmers a simple and flexible interface for developing parallel applications.

The materials used in this course were developed using Microsoft PowerPoint by Dr. Dave Ennis of OSC and first delivered in conjunction with this project. They include the following sections:.

  1. Introduction
  2. MIPS R10000 Processor
  3. Origin 2000 Architecture
  4. Processes and Load Sharing
  5. OpenMP Parallel Programming
  6. Data Distribution Directives
  7. Automatic Parallelization
Ater discussions of the processor, architecture, and creation and scheduling of parallel threads, the OpenMP directives were presented in detail along with examples of their use.  The course concluded with an equally important topic of how to distribute the data used by parallelized OpenMP regions amoung the local memories on the Origin 2000.

The notes were projected on a screen at the front of the classroom, using a projector attached to an instructor computer station which runs a Web browser to display the HTML version of the notes. Local and remote attendees were given the option of following along using either a hard copy of the notes or the online HTML notes using the Tango Interactive shared web browser on the classroom workstations.

TANGO Interactive

The software infrastructure used to deliver this course content simultaneously to several sites over the Internet is TANGO Interactive, from the Northeast Parallel Architectures Center (NPAC) at Syracuse University. This software consists of a plugin for the Netscape Navigator Web browser and several Java, Javascript, and native (i.e. compiled C++) collaborative applications. The TANGO suite allows applications to be shared between users in a master/slaves or peering collaboration.

To use TANGO, the user first connects to a web page containing a Javascript applet which brings up a TANGO startup window (shown in Figure 1). This allows the user to select the interface (the set of shared applications available) as well as the TANGO collaboration server to which to connect. This TANGO server need not reside on the same system as a Web server, although it is often convenient to colocate the two. Once the user selects a collaboration server and interface, he or she is presented with a login window (shown in Figure 2) where they can enter an identifier for themselves. Once an identifier is entered, the user is presented with the TANGO control application (shown in Figure 3), which is used to initiate sessions of shared applications or to connect to already existing sessions.

There were four TANGO applications used in the two distance trainings: shared browser, Buena Vista, chat, and whiteboard. The first of these, the shared browser, is a normal Netscape Navigator window, except that it tracks the current URL in the shared browser window of the user who is the master of the shared browser session. When the master user's shared browser moves to a new URL, the shared browser of all the other users in that session also move to the new URL. The shared browser is designed so that only the URL is shared through the TANGO framework, and each browser loads the URL as if it had been typed in locally.  This makes it possible WWW caches at recipient sites to reduce the bandwidth consumed over the long-haul networks.

The second TANGO application used for these classes was the Buena Vista audio/video conferencing software. Buena Vista is a two-way streaming audio and video conferencing tool which can be run in either full or half duplex ("click to talk"), though in most cases so far, the half-duplex mode has been used based on practical site considerations, described in more detail below.  Versions of Buena Vista are available for Intel based PCs as well as SGI workstations, and the two versions are completely interoperable. For the Fortran 90 workshop, Buena Vista was used to deliver a "talking head" consisting of audio and video streams of the instructor's lectures to the remote sites, as well as the facilitation of discussions between the instructor and remote attendees.  During the OpenMP training, video was not used.

The third TANGO application was the chat client (shown in Figure 4). This is a fairly conventional chat program, similar to many IRC (Internet Relay Chat) clients. The chat tool provides a mechanism for students at remote sites to pose questions without worrying about audio configurations, and for support personnel to discuss and handle technical problems with minimal intrusion on the class itself (using a separate instance of chat from the ones the students and instructor use).

The final TANGO application used in these classes was the whiteboard (shown in Figure 5). The whiteboard is a shared vector drawing package, which was used to display diagrams and example code fragments.

For the OpenMP class, an additional TANGO application was used experimentally.  This was a shared telnet session, designed to allow instructors to share a live telnet session with students for demonstration purposes during a lecture, or during a hands-on laboratory session to allow students to show the instructor problems they are having when asking for assistance.  The tool was a prototype, created by interfacing an existing Java telnet/terminal emulator to the TANGO system.  For security purposes, it was designed so that keyboard input was accepted only from the master instance of the tool, with the others displaying only the characters returned from the remote host.  In a hands-on lab setting, the idea was that students would each have their own separate (not shared) telnet session, and when they needed to consult with the instructor they would use TANGO to launch a copy of their session to the instructor's workstation.  The tool was used briefly by the instructor during a demonstration; due to time constraints, there was insufficient time to try to use it in the hands-on laboratory environment.

Except for Buena Vista, the TANGO applications used in these trainings require minimal bandwidth, on the order of 10 kB/s or less. Buena Vista, because it does synchronous audio and video streaming, requires considerably more bandwidth depending on the quality of the audio and video streams generated. The TANGO developers recommend that for best results, networks should be able to sustain 100 kB/s with minimal latency or jitter. As will be seen below, this can be difficult to achieve over the "commercial" Internet backbone, but is generally available on the DREN (Defense Research and Engineering Network), to which most would-be PET training recipients are connected.

Classroom and Network Configuration

Both classes were presented by OSC instructors in the Training and Education Facility (TEF), located in the Information Technology Laboratory (ITL) at the Army Corps of Engineers Waterworks Experiment Station (CEWES) Major Shared Resource Center (MSRC) in Vicksburg, Mississippi. This classroom is outfitted with SGI Indy workstations at each of the student desks and an SGI O2 workstation at the instructor desk. The O2 is connected to a projection system which projects an image of the O2's display onto a screen at the front of the classroom; it is also equipped with a digital video camera and a headset microphone, as well as a PA system and analog video cameras for capturing classes on videotape.

The second classroom for these classes was the "Fishbowl", located at the Ohio Supercomputer Center (OSC) in Columbus, Ohio. This classroom is configured similarly to the TEF at CEWES, except that the student workstations are mostly SGI O2s rather than Indies. There is also no analog video camera in the Fishbowl.

During the first training, an ??? workstation at the Army Research Laboratory (ARL) MSRC served as the other remote recipient. For the second training, ARL made use of their training room, located at the HEAT Center, which is equipped with SGI O2 workstations.

Other participants in the second training were the Aeronautical Systems Center (ASC) MSRC at Wright-Patterson Air Force Base (WPAFB) in Dayton, Ohio, the Naval Oceanographic Office (NAVO) MSRC at the Stennis Space Center in Mississippi, and the Naval Research Laboratory (NRL) in the District of Columbia.  ASC and NAVO used SGI O2 workstations in their training rooms, while NRL used two WindowsNT systems. Both classes were also monitored at NPAC for support purposes.

All four MSRCs and NRL are connected to the Defense Research and Engineering Network (DREN) backbone, shown in Figure 6. Network traffic between NPAC or OSC and the DREN sites was carried partly over the commercial Internet.  Through its work with Jackson State University, NPAC has been able to work with Syracuse University's Internet service provider and DREN staff to obtain an efficient routing of network traffic from NPAC to the DREN (JSU's distance education classroom is connected by a T-1 link to the CEWES MSRC, and is part of the DREN).  The distance trainings made use of the same routing, so network performance to NPAC was not a problem.  However OSC, which did not have any historical special arrangements, suffered from some degredation of audio performance during the later afternoon, when the Internet is most heavily loaded.
 

Preparation and Support

Part of the original design of this project was the use of centralized training facilities with local support staff knowledgable in the computer hardware and software configurations available.  Our concern was two-fold: first, proper setup of TANGO, particularly the audio/video conferencing system (BuenaVista), while not terribly complicated does require some attention; second, we felt it was important to have someone at each site with at least a basic familiarity with TANGO and the distance training setup to assist students and handle problems that might crop up during course delivery.

Familiarity with TANGO was developed in two ways. Although it was not required, some of the local support staff (from ARL, CEWES, NAVO, and OSC) were able to attend trainings offered by NPAC staff on the installation, operation, and support of TANGO.  Before each of the two trainings, we also undertook a number of test sessions involving site support staff and the instructor with the dual purpose of increasing the experience and familiarity of everyone involved with the distance delivery setup and the particular tools and techniques that would be used to deliver the class, and to try to identify in advance any potential problems with the hardware and software configurations at each of the sites.  Two or three advance tests were held before each training, each test lasting from 30 to about 90 minutes.  Typically the first test was designed to get all of the sites connected with at least one workstation and to run through the specific tools that the instructor planned to use during the class to insure that they were operational at all sites (we experienced several problems due to the use of different versions of Netscape Navigator at different sites which were identified during these tests, and handled by reverting to a simpler version of the tool in question).  This gave all sites a working installation, which they could then replicate on the rest of their computers.  The second test was originally intended to allow sites to double check the configuration of the remainder of their systems, though in fact it was not really used in this way.  Primarily, it served as an opportunity to develop more experience among the sites involved.

Problems Encountered

One problem encountered during the testing phase in advance of the second training was that different sites were running different versions of Netscape Navigator.  Certain of the recently-developed TANGO applications ("interactive chat" and "object-oriented whiteboard") have problems due to bugs in some releases of Navigator.  Since it was not practical for all sites to upgrade to the latest version of Navigator, we fell back to earlier versions of the tools in question which did not suffer the same problems ("simple chat", "paint").  This was a minor but noticable inconvenience to the instructor, who was expecting to use the newer versions of the tools.

Several problems with TANGO and the network infrastructure were experienced throughout the workshop. Some of these problems were caused by high latencies, while others were caused by application bugs or in one case a server being down. Though not the fault of TANGO per se, these problems made it difficult to get consistent performance out of the TANGO applications, especially Buena Vista.

The first problem, seen about an hour before the workshop started, was that NPAC's web server (trurl.npac.syr.edu) was down during part of the morning of the workshop. This caused problems with OSC's TANGO installation, which expected to be able to download the TANGO startup web page from the NPAC web server. Luckily, this necessary web page was replicated on the CEWES TANGO server (tango.wes.hpc.mil), and the OSC installation of TANGO was temporarily modified to use the CEWES version of the page instead of the NPAC version.

An ongoing problem throughout the day was the network congestion seen between OSC and CEWES. This became progressively worse as the day wore on and the public Internet backbones became saturated from cross-continental network traffic. This caused the downloading of applets and web pages to slow to as low as 3 kB/s. It also created problems with Buena Vista such that no one at OSC who joined the workshop's Buena Vista session after 10am (EDT) was able to get both audio and video streams to work consistently. OSC had multiple BV clients running, so in this instance, transmissions in a multicast anner would have been preferred.  To alliaviate this problem, only one BV client was used during the second course.

Another Buena Vista problem, unrelated to network performance, was that the SGI version of Buena Vista initally overrides the current audio settings of the workstation and sets the output/speaker level to between 90 and 100 percent of maximum. This can cause discomfort or potentially even hearing damage for users wearing headphones. It can also lead to acoustic feedback problems on systems where a microphone is set to transmit.

Due to an equipment problem at OSC immediately prior to the start of the OpenMP training, there was a problem with audio echoing due to switched cables through the sound mixer at OSC.  The problem was diagnosed and resolved during the first hour, but it was annoying to the participants until it was fixed.

Another audio-related problem that occurred only during the second training was a series of "drop-outs", where ARL lost the audio feed.  These drop-outs either ended without intervention after a period of 20-60 seconds or the ARL BuenaVista client was restarted to restore audio.  While obviously disruptive for the ARL students, and generally undesirable, we have been unable to reproduce, or even adequately explain the problem.  In several years of using BuenaVista, we have never experienced such a problem before, and in this case it was only ARL that experienced the problem.  This rules out problems with the transmitting client (at CEWES), which should have randomly affected all receiving clients.  Nor is there any evidence that there were network problems between CEWES and ARL. The possibility that there was a problem with the receiving workstation at ARL was not investigated.

Student Reactions

Fortran 90

Much of the confusion surrounding the TANGO format centered on getting the software loaded and configured. When students entered the classroom, they were
given a logon account, password and a instruction sheet on how to load TANGO. The local instructor went through the TANGO procedure before class, but
students who arrived late missed out on the TANGO walkthrough.

Once connected and observing the lecture, students did not seem to have any problems. They did seem to benefit from the video image of the instructor as his hand
movements did add clarification. Most seemed comfortable with the headsets and audio settings, once they were shown how to bring up the audio panel that
contained the volume setting. The audio quality was good, while the video image was of marginal quality. The quality of image did not seem to bother the students a
great deal. Some asked if it could be improved, but seemed satisfied when they found out that it could not.

A few students lost their Buena Vista session midway through the course and were unable to reconnect. As discussed above, full BV sessions could not be
established after approximately 11 am. This did create some problems as once students became used to the video image, they had difficulty adjusting to it's absence.

Students also appeared uncomfortable asking questions via the TANGO tools. To avoid background noise, the mics were turned off when students were asking
questions. Since there was no mute switch on the headsets, they had to stop and start Buena Vista audio or adjust the mic input lever in the audio panel to activate
their mic to talk. Usually by the time they got ready to ask the question, the instructor moved on to new material. The natural network delay was also a detriment. The
students did not feel comfortable interrupting the instructor. If the instructor paused and asked for questions, they seemed more willing to speak up. Posting questions
to the chat window and having the instructor address them at his convenience might be a better approach.
 

Parallel Programming on the Origin 2000 using OpenMP

For the second course, support staff prepared student workstations by preloading TANGO prior to each day of the course.  Instead of having the students responsible for connecting to the appropriate applications, connections were the responsibility of the instructor.  For students entering late, support staff provided assistance.  Also, only one BV application ran from the instructor workstation alliviating many of the student reactions encountered during the first course.

All remote questions were received through the chat application.  In this instance, students asked a multitude of questions.  Video showing the remote classrooms may have enhanced this process as some students at other locations would have preferred less emphasis on certain topics.  Through video, the instructor could visually survey the majority of students and focus on their reactions..

Instructor Reactions

Fortan 90

The instructor's reactions to this teaching environment were mixed. While the TANGO tools were generally effective in delivering the course content, answering remote questions was time consuming.  Simultaneously repeating questions so all the students could hear and formulating responses extended the class time and burdened the instructor.

The TEF classroom environment was such that it was difficult for the instructor to pay the same attention to the local users as the remote users. The O2 instructor workstation in the TEF was at a right angle to the main axis of the classroom. The instructor had to choose between facing the workstation and its digital camera and "ignoring" the local class, or facing the local class and "ignoring" the remote students. This was especially problematic when questions were asked from remote sites via the chat window.

Parallel Programming on the Origin 2000 using OpenMP

Prepare less material for a tango session due to delays caused by mechanical/software problems.  The awkward mechanism for pointing out sections of a slide and rereading the questions out loud from the chat tool provided additional delays. The net effect is that there was virtually no time for the students to do the labs, except on their own time.  It was necessary to ruch through the penultimate chapter and completely skip the final chapter.

Improvement is needed for students to ask questions.  The instructor would have prefered an audible sound denoting when a question is entered into the chat window.  Unfortunately, this feature was available unbeknownst to the instructor.  An alternative solution would include a portable microphone at each site that questioning students could pass around.

A shared pointer is highly desirable. For the remote participants, it was necessary to explicitly refer them to important information on the slide by saying something like "If you look at the fifth bullet from the bottom, it contains an important point...".  The extended verbage extended lecture time. This capability is available in WebWisdom and WebWisdomNT (the later of which will be packaged and integrated with TANGO soon).

Need ability to increase the font size on the shared telnet application.  For those attendees viewing from a main screen, the default font size was too small.  This limited demonstrations. A shared X Window application would provide the means to demonstrate many of the system's software tools with graphical user interfaces. There are plans to integrate VNC, which is like X but cross-platform.

Provide a tool to annotate materials.  The instructor used the shared browser tool to display the materials and the shared whiteboard for handwritten information and would have preferred a viewing tool that he could annotate.  This is coming with WebWisdomNT

Tango support knowledge on-site is critical.

Conclusions

Lessons Learned

Take note of different time zones.

Recommendations

Future Directions

Based on the results of this project, we plan to make distance training delivered with TANGO a more or less routine part of the CEWES PET training program.  Initially, this will primarily involve expanding the group of instructors and course offerings.  Organized trainings will be offered to help acquaint new instructors with the tools and techniques, and they will be required to participate in preparatory trial deliveries before their first actual distance training.  To facilitate an appropriate level of support for these trainings, we expect to continue to emphasize delivery to training rooms, however we do plan to begin some experiments with direct to the desktop delivery with carefully selected individuals.

Based on feedback from these trainings, as well as other experiences, a number of enhancements to TANGO are in progress or planned which address many of the issues raised here. (Some were in fact under development before these trainings, but had not reached a deployable state in time for use here.)  One of the most significant advances coming is WebWisdomNT, a sophisticated database-backed tool for the management and presentation of courseware.  This tool will provide the shared pointer and annotation capabilities noted by the instructors (students will also be able to store their own annotations using WebWisdomNT).  Also, an "educational" version of BuenaVista is under development which will give the instructor access to  all student controls, which will make it easier to utilize audio for interaction (on appropriately setup workstations) with less demand on the local support staff or students to be familiar with the details of the audio system's operation.

Acknowledgements

The authors wish to thank the support staff at the recipient sites for their very important help in making this project a success and for their critical readings of the manuscript:  Brian Cladwell, Mason Colbert, John Eberle, Derek Moses, Tracey Smith, Brian Tabor, and also Marek Podgorny and the TANGO group.

This work was funded (in part) by the DoD High Performance Computing Modernization Program at the U.S. Army Corps of Engineers Waterways Experiment Station (CEWES) Major Shared Resource Center through Programming Environment and Training (PET) through contract DAHC94-96-C-002 with Nichols Research Corporation. The major delivery technology, TANGO Interactive, was initially developed with funding from Rome Laboratory.

Figures

TANGO Startup Window
Figure 1: TANGO Startup Window

TANGO Login Window
Figure 2: TANGO Login Window

TANGO Control Application
Figure 3: TANGO Control Application

TANGO Chat Client
Figure 4: TANGO Chat Client

TANGO Object Whiteboard
Figure 5: TANGO Object Whiteboard

DREN Connectivity Map
Figure 6: DREN Connectivity Map

Appendices

Guidelines for Distance Training with TANGO Interactive

These guidelines have been developed based on the experience gained from both academic and training course delivery over the past several years, including the training experiments described in this paper.  They are intended to help would-be instructors, students, delivery sites and recipient sites better understand some of the important requirements and factors which, based on our experience, will help produce successful distance trainings delivered with TANGO Interactive.

For Instructors

For Students

For Delivery and Recipient Sites

Hardware Requirements/Recommendations
Software Requirements/Recommendations
Other Guidelines

General Comments

Student Evaluations