Workstation VTC and Collaborative Computing over
GCCS LES Test Bed
DRAFT - November 20, 1995
The MITRE Corporation
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
- Local Backbone is ATM
- Transmission to remote sites is also ATM
- Transmission protocol is Internet Protocol (IP).
- Workstation alternatives are:
- Pentium w/windows NT
- Sun Sparc w/Solaris 2.4
- HP w/ HP/UX 9.07 min.
3. Desired Conferencing Attributes
- Video Conferencing (multipoint motion video with audio)
- Multimedia Desktop (Common White board and Applications sharing)
- Interactive Distance learning
- "Dial-up" capability
- Spontaneous capability
- Video on demand
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.
- Limited COTS products for VTC over Ethernet are available but do not
provide full ITU-TSS compliance for H.320.
- The standard for VTC over ATM is brand new. Products meeting this
standard are just being developed.
- Some board-level CODECs have been developed to support the H.261 compression
standard but do not meet the full set of H.320 standards.
- Availability of COTS products meeting T.120 for operation over ATM appears
to be very limited at this time.
- The DataBeam Corporation collaborative computing product called FarSite
meets T.120 standards but has limited operation over ATM.
- Manufacturer's application products supporting IP over ATM need to be
identified and tested. MITRE is continuing to identify and evaluate these
products as they become available. Several products are expected in calendar
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
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.
- USACOM ATM information (MITRE Informal Memo) [Unavailable]
- Information on First Virtual Corporation Multimedia over ATM [Unavailable]