The wide area telecom network

David Bonner continued, "We have been able to accomplish these connections and more. Now we can see the network providing voice as well as video and data across the same IP network".

The solution for connectivity was the flat rate Frame Relay service provided by Bell Atlantic-Nynex. This was chosen because it was available in remote areas and inexpensive. Partners access the network through a private virtual connection (PVC). Cost to the user is a function of minimum speed and is substantially less than ISDN because the Frame Relay cloud is shared.

An ATM backbone has been installed at the University Heights Complex in Albany. This links the Albany Medical Centre, the Albany Medical College, The Albany Pharmacy School, the Law School, and the Sage Colleges at Troy. Cisco and RioTech have helped to build the campus backbone which uses CISCO routers and switches.

In September 1997, Nynex will bring two T3s to the University Heights complex. One will be linked at the Albany Medical College and the other will come out at Sage Colleges. This will provide true redundancy over the ATM backbone. If one T3 goes down, the other can be used.

So that whilst the network uses Frame Relay for connectivity, there is a hybrid cloud in the sense that it includes ATM, Token Ring, Fast Ethernet, lO-BaseT, and ISDN. But it is Frame Relay that is the backbone to the remote areas.

The videoconferencing network

The Network uses a novel approach to transporting video over frame relay. Extensive use is made of RADVision Video Interface Unit (VIU). These take an H.320 stream and change it into an lP-encapsulated H.323 stream.

The RADVision VIU can be used with any videoconferencing system to convert the video to run on an IP network. It is widely used to adapt group systems to run on a LAN.

The network also uses a RADVision Gateway, which is basically a PBX that allows ISDN head-ins into the Frame Relay cloud. The Gateway converts IP addresses to typical video phone numbers for ISDN connections. There are several of these Gateways deployed in the cloud.

Since it is an IP network, a video phone call goes to the Gateway and gets translated into an IP address which can pass over the network's routers.

David Bonner says "The end user does not feel that all this is going on. It just goes to its proper SPID on the network and the video connection is made. So it would not matter whether you are using Frame Relay, ATM, or ISDN as the transport from one town to the next."


Th Adirondack Area

The videoconferencing equipment used

The Adirondack Area Network has a lot of equipment. Compression Labs Inc. (CLI), which is now merged into VTEL, helped with early pilots as did-RADVision. Beta testing of equipment started in January 1997 and now that the network is up and running, new equipment is added almost every week.

There is a VideoServer Unit (MCS) at Troy, N.Y. But this will be moved soon to Albany and become the hub for multi point conferences.

There are 12 room systems in New York State and a further 28 in Vermont. These are from VTEL and VCON. The medical sites use a number of VTEL's FRED systems which are roll-about units designed for health care facilities.

The Vermont network was a pure ISDN network but has now changed to the Adirondack Area Network technologies. In regard to the number of desktop systems, Dr. David Bonner said the number will soon be hundreds with 150 partners.

To convert a room system to run on the LAN and then over Frame Relay, a RADVision Video Interface Unit is used to convert the H.320 signal to H.323. "We have made extensive use of RADVision VIUs", Dr. David Bonner told us.

Applications for videoconferencing

One of the principal users of video conferencing is the Albany Medical Centre, a teaching hospital and the Albany Medical College. There the Director of Network Services is Dan Maloney.

Dan told us "we are doing more and more telemedicine. Albany Medical Centre has been involved for some time. We are moving out aggressively now that we have a platform."

He continued "Some of the directions we are moving in are transmission of radiology -whether that be X-Rays, CAT scans or ultrasound attachments. We transmit them either digitally or using a document camera or Elmo unit. We are looking at ways of bringing telemedicine into the homes of senior citizens, for example by remotely using otoscopes, stethoscopes & EKG machines.

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