Workstation VTC and Collaborative Computing over GCCS LES Test Bed

DRAFT - November 20, 1995
The MITRE Corporation
Informal Paper
Charles King

1. Introduction

The following information is the result of a short review of workstation products that will support desktop (personal) video teleconferencing (VTC) and collaborative computing for use with Asynchronous Transfer Mode (ATM) transmission services. ATM is the formal ITU (previously CCITT) standards supporting cell-based voice, data, and multimedia communication in a network under Broadband Integrated Services Digital Network. The connection-oriented service permits switched virtual connections that, once established, remain in place thereby supporting video and other real-time information services. During this review it was found that there are very few commercial off the shelf (COTS) products established that presently support standards-based conferencing over the ATM transmission media. Communication formatting standards for compressed video have been only recently established for ATM, therefore, this technology is in a state of fluctuation and is expected to stabilize with mature COTS products becoming available over the next one to two years.

There are two principal recommendations: (1) leverage on the lessons learned by the United States Atlantic Command in Norfolk VA in the installation of their ATM LAN/WAN capability as part of the Defense Information System Network (DISN) Leading Edge Services (LES), and (2) the initial purchase of application products to be tested should be of limited quantity until mature standards-based products are identified and fully tested and accepted by the users.

2. Fixed Requirements

3. Desired Conferencing Attributes

4. Desired Standards

H.32X set of standards supporting video conferencing. The International Telecommunications Union - Telecommunication Standardization Sector (ITU-TSS) has created a set of international standards (actually recommendations), sometimes called px64, which fall under the umbrella standard H.320 entitled Narrowband Visual Telephone Systems and Terminal Equipment. One of the most recently ratified standards is H.321 which provides guidance for operation over ATM networks. Some of these recommendations include H.3261 Video Compression; H.221 Frame Structure for Audio Visual Services; G.711, G.722, and G.2728 Audio Compression; H.231 Multipoint Control Services; and H.233 DES Encryption.

T.120 set of standards for common whiteboard and applications sharing. The T.120 standard was also created by the ITU-TSS and consists of a set of recommendations covering a series of communication and application protocols and services supporting real-time, multipoint data communications. One of its principal applications is collaborative computing. Some of these recommendations are T.122 Multipoint Communication Service, T.123 Network Specific Transport Protocols, T.124 Generic Conference Control, and T.126 Still Image Exchange. While the majority of the T.120 standard has been ratified, some areas within the set of recommendations are still being finalized.


6. Product Examples

PictureTel Corporation Model PCS 100. PictureTel has announced a new product in collaboration with First Virtual Corporation (FVC) for running their PCS 100 workstation-based product, which meets the H.320 VTC standard, over ATM. This product supports both VTC and information sharing software including common white board common viewing of documents. An advanced specification sheet is attached. The workstation platform that this product presently uses is the same platform used by the PictureTel PCS-100 standard product which is a PC running Windows 3.1. The product presently does not run under the NT operating system and no target date has been provided. The FVC product sets up a guaranteed ATM pipeline through their Media Operating System for supporting both the real time video and collaborative software provided by the PCS 100 product. The product supports an ATM LAN/WAN or ATM LAN to ISDN interface. ATM interfaces are being developed for multipoint control units (MCUs) to support multipoint VTC using the PCS 100. Note: a similar capability is expected to be available in the near future from the VTEL Corporation. Contacts are Craig Kielman of PictureTel 714-0273 and Howard Moser of First Virtual 212-858-7515.

InSoft Communique. InSoft confirms that their present Communique product will run over ATM and has been tested by DISA. A standards-based product is available for a Hewlett Packard (HP) workstation. The HP configuration runs on HP UX at 9.07 and can use the H.261 HP video encoder/decoder (CODEC) or the Parallax video board. Their primary product, Communique 4.1, uses the Parallax video processing board and a Sun SPARC 10 or SPARC 20 workstation running Solaris 2.4. A product supporting a PC platform is also available The Sun and PC implementations are non H.320 standards-based products as the Parallax board uses the Joint Photographic Experts Group (JPEG) compression algorithm. InSoft is under contract by the Joint Project Office (JPO) to demonstrate a standards-based product using a video CODEC board manufactured by IMS Inc. To date, the attempt to integrate the IMS video board into the InSoft product has not worked. InSoft is expecting an updated version of the IMS video board and associated software shortly. The InSoft contact is Bob O'Gorman at 749-0584.

PVSC (Paradise Software Inc.) The Paradise product is non standards based. The Paradise VTC software is presently being evaluated by the Atlantic Command (ACOM) over their ATM network. The ACOM test is being conducted on a Sun workstation. The MITRE Corporation Command and Control Engineering Lab (CCEL) has also evaluated this product. An applications sharing package for collaborative work was not available as part of the PVSC package. In addition, MITRE found that the CPU utilization time was very high on this product.

DataBeam Farsite. This product is one of the few products supporting shared whiteboard and the T.120 standard. Farsite currently will run on PCs using Windows 3.1 and Windows 95 and on a Sun SPARC-compatible device using Sun OS. Some of the FarSite functions will operate under Windows NT. FarSite can run on LAN/WAN connections using TCP/IP or IPX. While FarSite will run over ATM, presently, it does not take advantage of the Isochronous capabilities of ATM. Once the T.123 network specific protocols for ATM are in place (1996) an improved capability should be available.

Table 1 Product Overview

Product    H.320   Whiteboard/ Shared   T.120   Support ATM  Available      
PCS 100      x       x                            x          Now            
InSoft     Partial   x                            x          Now            
PVSC                                              x          Now            
FarSite              x                    x       x          Now *          
* Per DataBeam, no customer implementations over ATM were identified.

7. ACOM ATM Communications Backbone.

An ATM internal backbone, supporting a Client Server based architecture, has been installed at the Atlantic Command as an implementation under DISN Leading Edge Services (LES). The capability is operational with connections between Norfolk and several remote sites, including US Forces Command in Atlanta GA and the Washington D.C. Navy Yard, principally for data transmission. The configuration uses Fore products. Attached to this report is a short informal report that discusses the ACOM configuration including a list some of the Fore products purchased and installed and some of the problems encountered with this installation. Also included are two configuration drawing and one drawing that illustrates the DISN LES network. Contacts are Joe Jackson and Al Galgano (MITRE) 804-322-7322 and Ralph Carmines (Naval Intelligence Center) 804-322-7311.

8. Conclusions and Recommendations

No mature COTS products were identified for providing standards-based (H.320 and T.120) desktop VTC with collaborative computing.

The InSoft Communique product, although not standards based, remains a viable product for test bed demonstration and test. However, because of the lack of interoperability with other manufacturer's products, a limited initial deployment is suggested. Standards-based COTS products may force obsolescence of such test products within 2 years.

It is recommended that a one-day visit to the intelligence center at CINCUSACOM be conducted to review the ACOM ATM LAN and WAN installation. This would allow the Slidell LA test facility to leverage on lessons learned at this installation and assure the development of a compatible capability. This visit should be coordinated with Mr. Ralph Carmines.

If the PC platform with Windows is acceptable, the PictureTel product should be tested as it is the only standards-based VTC product identified. The collaboration package, called LIVE Share, does not meet the T.120 standard at this time.

Continue to track and evaluate emerging products that will support standards- based VTC and collaborative computing over ATM including continuing product development by PictureTel, VTEL, and DataBeam.

9. Attachments: