Editor's Note: The Alliance is currently developing and deploying technologies to build and support the National Technology Grid. The three thrust activities involve collaborations with other groups establishing similar grid environments. The Alliance is working with NPACI, NASA IPG, and Argonne National Lab to increase the services available to the national high-performance user community. Three issues of data link are providing background information about the thrust areas: Virtual Machine Room in May, the user portal in June, and the Access Grid in July.

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Access Grid Complements Computational Grid

Ask different people what they think the Access Grid is and you get different answers. The developers' website says the Access Grid is "an ensemble of resources that can be used to support human interaction across the grid." The chancellor of the Ohio State Board of Regents recently reflected at an Alliance Chautauqua 2000 held in Ohio that the Access Grid is a "virtual Petri dish," referring to the new opportunities for collaboration and contact it provides.

Clearly the Access Grid can be described in many ways, based on individual (or group) experiences. Developed at Argonne National Laboratory, the Access Grid (called AG for short) complements the computational grid being developed by the Alliance, NPACI, and other sites around the globe. The computational grid is the assembled hardware, software, and middleware that will offer unprecedented computational power to researchers. The AG provides for the human component of the grid, affording groups opportunities to interact in virtual meetings or conferences, to collaborate on remote visualizations, and to drive interactive applications.

AG and Nodes Explained

The AG consists of multimedia displays, presentation and interaction environments, and interfaces to middleware and visualization environments. Comprised of nodes located around the country, the AG supports large-scale distributed meetings, seminars and lectures, tutorials and other training events, and collaborative work sessions. Unlike desktop-to-desktop tools that primarily address individual communication, the AG nodes provide an opportunity for group-to-group communication. Depending on the venue in which a node is deployed, the groups can be quite large in number.

At the June Chautauqua in Ohio, the group assembled at the Fawcett Center for the conference numbered close to 100. Other nodes on the AG that participated included Boston University, the University of Kentucky, the University of Kansas, NCSA, Argonne, and the Albuquerque High Performance Computing Center. These sites easily added another 50 participants in the Chautauqua, people who could not make the trip to Ohio. Additional nodes are currently deployed around the US with other connections in the planning stages.

Technical and Human Challenges

Argonne and its Alliance AG partners have addressed many of the initial technology deployment and integration issues. The complexity – both technical and human – created by the burgeoning number of nodes points to the Alliance formalizing the requirements and processes necessary to install and operate an AG node.

One current hurdle to establishing an AG node is the need to acquire the components in piecemeal fashion. For more sites to join the AG, more formal and stable specifications of what it takes to establish a node is needed along with a process for updating and changing the specification. A core team to work with potential vendors to shrink-wrap AG node components is being assembled. This team, along with other working groups, will address related issues such as installation instructions, training for node operators and presenters, technical support, and administrative interplay between node sites.

Alliance PACS lead Frank Gilfeather, executive director of the AHPCC, pointed out that the AG changes certain social conventions. Speakers need to learn to poll participating sites for questions, for example. Frequently speakers are not facing the screen on which other AG nodes are displayed and therefore miss a hand waving in the air from a waiting questioner. Protocol on thanking a presenter was raised at the recent Chautauqua. Do all node site participants clap or just the "local" audience? By consensus, Chautauqua attendees agreed that everyone can clap. Because frequent movement by a presenter can result in a pixilated view at the node sites, the speaker is encouraged to stay relatively still at the lectern. The OSC staff created small placards reminding the speaker to stand still; other signs prompted the presenter to look for a question at a non-local site.

With the growing popularity of the AG, new opportunitites for new tools abound. The Electronic Visualization Laboratory at the University of Illinois at Chicago is developing AGAVE (Access Grid Augmented Virtual Environment), which is a virtual reality display for the AG. Developers are working on a way to share images and share control information throughout nodes. The EVL staff will augment the current AG specifications to offer 2 LCD projectors to provide front-projected, stereo images on a special screen, all viewed with inexpensive glasses to allow participants the virtual reality experience. A beta version is under development with initial deployment planned for a museum installation.

Seeing the AG in Action

To see the AG being used, consider signing up for the Alliance Chautauqua 2000 to be held August 1-3. The host site for this event is the University of Kansas but several other sites -- Boston University, ACCESS-DC, and NCSA -- will be enrolling participants.

For More Information

• the Alliance Chautauqua 2000 to be held in Kansas in August features use of the Access Grid
• Access Grid home page
• Assembling the Access Grid
• Access Grid used for PACS administrative meeting
• Presentations from the OSC Chautauqua, especially Frank Gilfeather's presentation entitled "Living on the Grid"